commit db5d46760a6b81da073ffb334606644d1674311a
Author: ilgazca <ilgaz.ca@gmail.com>
Date:   Wed Jul 30 16:12:03 2025 +0300

    first commit

diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 00000000..13566b81
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,8 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml
diff --git a/.idea/TimeSeriesAnalysis.iml b/.idea/TimeSeriesAnalysis.iml
new file mode 100644
index 00000000..e0d56747
--- /dev/null
+++ b/.idea/TimeSeriesAnalysis.iml
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="PYTHON_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$">
+      <excludeFolder url="file://$MODULE_DIR$/.venv" />
+      <excludeFolder url="file://$MODULE_DIR$/.venv1" />
+    </content>
+    <orderEntry type="jdk" jdkName="Python 3.13 (TimeSeriesAnalysis)" jdkType="Python SDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file
diff --git a/.idea/inspectionProfiles/profiles_settings.xml b/.idea/inspectionProfiles/profiles_settings.xml
new file mode 100644
index 00000000..105ce2da
--- /dev/null
+++ b/.idea/inspectionProfiles/profiles_settings.xml
@@ -0,0 +1,6 @@
+<component name="InspectionProjectProfileManager">
+  <settings>
+    <option name="USE_PROJECT_PROFILE" value="false" />
+    <version value="1.0" />
+  </settings>
+</component>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 00000000..019f0211
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Black">
+    <option name="sdkName" value="Python 3.13 (TimeSeriesAnalysis)" />
+  </component>
+  <component name="ProjectRootManager" version="2" project-jdk-name="Python 3.13 (TimeSeriesAnalysis)" project-jdk-type="Python SDK" />
+</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 00000000..8f155b37
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/TimeSeriesAnalysis.iml" filepath="$PROJECT_DIR$/.idea/TimeSeriesAnalysis.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 00000000..e69de29b
diff --git a/Uploads/airline_passengers.csv b/Uploads/airline_passengers.csv
new file mode 100644
index 00000000..e7eecfea
--- /dev/null
+++ b/Uploads/airline_passengers.csv
@@ -0,0 +1,145 @@
+"Month","Thousands of Passengers"
+"1949-01",112
+"1949-02",118
+"1949-03",132
+"1949-04",129
+"1949-05",121
+"1949-06",135
+"1949-07",148
+"1949-08",148
+"1949-09",136
+"1949-10",119
+"1949-11",104
+"1949-12",118
+"1950-01",115
+"1950-02",126
+"1950-03",141
+"1950-04",135
+"1950-05",125
+"1950-06",149
+"1950-07",170
+"1950-08",170
+"1950-09",158
+"1950-10",133
+"1950-11",114
+"1950-12",140
+"1951-01",145
+"1951-02",150
+"1951-03",178
+"1951-04",163
+"1951-05",172
+"1951-06",178
+"1951-07",199
+"1951-08",199
+"1951-09",184
+"1951-10",162
+"1951-11",146
+"1951-12",166
+"1952-01",171
+"1952-02",180
+"1952-03",193
+"1952-04",181
+"1952-05",183
+"1952-06",218
+"1952-07",230
+"1952-08",242
+"1952-09",209
+"1952-10",191
+"1952-11",172
+"1952-12",194
+"1953-01",196
+"1953-02",196
+"1953-03",236
+"1953-04",235
+"1953-05",229
+"1953-06",243
+"1953-07",264
+"1953-08",272
+"1953-09",237
+"1953-10",211
+"1953-11",180
+"1953-12",201
+"1954-01",204
+"1954-02",188
+"1954-03",235
+"1954-04",227
+"1954-05",234
+"1954-06",264
+"1954-07",302
+"1954-08",293
+"1954-09",259
+"1954-10",229
+"1954-11",203
+"1954-12",229
+"1955-01",242
+"1955-02",233
+"1955-03",267
+"1955-04",269
+"1955-05",270
+"1955-06",315
+"1955-07",364
+"1955-08",347
+"1955-09",312
+"1955-10",274
+"1955-11",237
+"1955-12",278
+"1956-01",284
+"1956-02",277
+"1956-03",317
+"1956-04",313
+"1956-05",318
+"1956-06",374
+"1956-07",413
+"1956-08",405
+"1956-09",355
+"1956-10",306
+"1956-11",271
+"1956-12",306
+"1957-01",315
+"1957-02",301
+"1957-03",356
+"1957-04",348
+"1957-05",355
+"1957-06",422
+"1957-07",465
+"1957-08",467
+"1957-09",404
+"1957-10",347
+"1957-11",305
+"1957-12",336
+"1958-01",340
+"1958-02",318
+"1958-03",362
+"1958-04",348
+"1958-05",363
+"1958-06",435
+"1958-07",491
+"1958-08",505
+"1958-09",404
+"1958-10",359
+"1958-11",310
+"1958-12",337
+"1959-01",360
+"1959-02",342
+"1959-03",406
+"1959-04",396
+"1959-05",420
+"1959-06",472
+"1959-07",548
+"1959-08",559
+"1959-09",463
+"1959-10",407
+"1959-11",362
+"1959-12",405
+"1960-01",417
+"1960-02",391
+"1960-03",419
+"1960-04",461
+"1960-05",472
+"1960-06",535
+"1960-07",622
+"1960-08",606
+"1960-09",508
+"1960-10",461
+"1960-11",390
+"1960-12",432
\ No newline at end of file
diff --git a/Uploads/processed_airline_passengers.csv b/Uploads/processed_airline_passengers.csv
new file mode 100644
index 00000000..7a05e6c7
--- /dev/null
+++ b/Uploads/processed_airline_passengers.csv
@@ -0,0 +1,145 @@
+Month,Thousands of Passengers,Trend,Seasonality,Residuals
+1949-01-01,112,,-24.74873737373736,
+1949-02-01,118,,-36.18813131313131,
+1949-03-01,132,,-2.2411616161616195,
+1949-04-01,129,,-8.036616161616166,
+1949-05-01,121,,-4.5063131313131395,
+1949-06-01,135,,35.40277777777778,
+1949-07-01,148,126.79166666666666,63.83080808080808,-42.62247474747474
+1949-08-01,148,127.25,62.82323232323231,-42.07323232323231
+1949-09-01,136,127.95833333333331,16.52020202020202,-8.478535353535335
+1949-10-01,119,128.58333333333331,-20.642676767676765,11.05934343434345
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+1949-12-01,118,129.75,-28.619949494949505,16.869949494949505
+1950-01-01,115,131.25,-24.74873737373736,8.49873737373736
+1950-02-01,126,133.08333333333331,-36.18813131313131,29.104797979797993
+1950-03-01,141,134.91666666666666,-2.2411616161616195,8.324494949494962
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diff --git a/app.py b/app.py
new file mode 100644
index 00000000..3dcd85cb
--- /dev/null
+++ b/app.py
@@ -0,0 +1,285 @@
+from flask import Flask, request, render_template, send_file, session
+import pandas as pd
+import io
+import os
+from statsmodels.tsa.seasonal import seasonal_decompose
+from statsmodels.graphics.tsaplots import plot_acf, plot_pacf
+import pmdarima as pm
+import plotly.express as px
+import plotly.graph_objects as go
+from plotly.subplots import make_subplots
+import plotly.io as pio
+from werkzeug.utils import secure_filename
+import matplotlib
+
+matplotlib.use('Agg')  # Use non-interactive backend
+import matplotlib.pyplot as plt
+import io
+import base64
+import numpy as np
+
+app = Flask(__name__)
+app.config['UPLOAD_FOLDER'] = 'Uploads'
+app.config['ALLOWED_EXTENSIONS'] = {'csv', 'xls', 'xlsx'}
+app.secret_key = 'your-secret-key'  # Required for session management
+
+# Ensure upload folder exists
+os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
+
+
+def allowed_file(filename):
+    return '.' in filename and filename.rsplit('.', 1)[1].lower() in app.config['ALLOWED_EXTENSIONS']
+
+
+def create_acf_pacf_plots(data):
+    # Create ACF and PACF plots using matplotlib
+    fig, (ax1, ax2) = plt.subplots(2, 1, figsize=(10, 8))
+
+    plot_acf(data, ax=ax1, lags=40)
+    ax1.set_title('Autocorrelation Function')
+
+    plot_pacf(data, ax=ax2, lags=40)
+    ax2.set_title('Partial Autocorrelation Function')
+
+    # Convert matplotlib plot to Plotly
+    buf = io.BytesIO()
+    plt.savefig(buf, format='png')
+    plt.close(fig)
+    buf.seek(0)
+    img_str = base64.b64encode(buf.getvalue()).decode('utf-8')
+
+    # Create Plotly figure with image
+    fig_plotly = go.Figure()
+    fig_plotly.add_layout_image(
+        dict(
+            source=f'data:image/png;base64,{img_str}',
+            x=0,
+            y=1,
+            xref="paper",
+            yref="paper",
+            sizex=1,
+            sizey=1,
+            sizing="stretch",
+            opacity=1,
+            layer="below"
+        )
+    )
+    fig_plotly.update_layout(
+        height=600,
+        showlegend=False,
+        xaxis=dict(visible=False),
+        yaxis=dict(visible=False)
+    )
+    return pio.to_html(fig_plotly, full_html=False)
+
+
+def process_time_series(filepath, do_decomposition, do_forecasting, do_acf_pacf, train_percent, forecast_periods):
+    try:
+        # Read file
+        if filepath.endswith('.csv'):
+            df = pd.read_csv(filepath)
+        else:
+            df = pd.read_excel(filepath)
+
+        # Ensure datetime column exists
+        date_col = df.columns[0]  # Assume first column is date
+        value_col = df.columns[1]  # Assume second column is value
+        df[date_col] = pd.to_datetime(df[date_col])
+        df.set_index(date_col, inplace=True)
+
+        # Initialize variables
+        plot_html = None
+        forecast_html = None
+        acf_pacf_html = None
+        summary = df[value_col].describe().to_dict()
+        arima_params = None
+        seasonal_params = None
+        train_size = None
+        test_size = None
+
+        # Save processed data
+        processed_df = df.copy()
+
+        # Time series decomposition
+        if do_decomposition:
+            decomposition = seasonal_decompose(df[value_col], model='additive', period=12)
+            fig = make_subplots(rows=4, cols=1,
+                                subplot_titles=('Original Series', 'Trend', 'Seasonality', 'Residuals'))
+
+            fig.add_trace(go.Scatter(x=df.index, y=df[value_col], name='Original'), row=1, col=1)
+            fig.add_trace(go.Scatter(x=df.index, y=decomposition.trend, name='Trend'), row=2, col=1)
+            fig.add_trace(go.Scatter(x=df.index, y=decomposition.seasonal, name='Seasonality'), row=3, col=1)
+            fig.add_trace(go.Scatter(x=df.index, y=decomposition.resid, name='Residuals'), row=4, col=1)
+
+            fig.update_layout(height=800, showlegend=True)
+            plot_html = pio.to_html(fig, full_html=False)
+
+            processed_df['Trend'] = decomposition.trend
+            processed_df['Seasonality'] = decomposition.seasonal
+            processed_df['Residuals'] = decomposition.resid
+
+        # Forecasting
+        if do_forecasting:
+            # Split data into train and test
+            train_size = int(len(df) * train_percent)
+            test_size = len(df) - train_size
+            train_data = df[value_col].iloc[:train_size]
+            test_data = df[value_col].iloc[train_size:] if test_size > 0 else pd.Series()
+
+            # Auto ARIMA for best parameters
+            model = pm.auto_arima(train_data,
+                                  seasonal=True,
+                                  m=12,
+                                  start_p=0, start_q=0,
+                                  max_p=3, max_q=3,
+                                  start_P=0, start_Q=0,
+                                  max_P=2, max_Q=2,
+                                  d=1, D=1,
+                                  trace=False,
+                                  error_action='ignore',
+                                  suppress_warnings=True,
+                                  stepwise=True)
+
+            # Fit ARIMA with best parameters
+            model_fit = model.fit(train_data)
+            forecast = model_fit.predict(n_periods=forecast_periods)
+
+            # Get ARIMA parameters
+            arima_params = model.order
+            seasonal_params = model.seasonal_order
+
+            # Forecast plot
+            forecast_dates = pd.date_range(start=df.index[-1], periods=forecast_periods + 1,
+                                           freq=df.index.inferred_freq)[1:]
+            forecast_fig = go.Figure()
+            forecast_fig.add_trace(go.Scatter(x=df.index, y=df[value_col], name='Historical'))
+            if test_size > 0:
+                forecast_fig.add_trace(
+                    go.Scatter(x=df.index[train_size:], y=test_data, name='Test Data', line=dict(color='green')))
+            forecast_fig.add_trace(go.Scatter(x=forecast_dates, y=forecast, name='Forecast', line=dict(dash='dash')))
+            forecast_fig.update_layout(title=f'Forecast (ARIMA{arima_params}, Seasonal{seasonal_params})', height=400)
+            forecast_html = pio.to_html(forecast_fig, full_html=False)
+
+        # ACF/PACF plots
+        if do_acf_pacf:
+            acf_pacf_html = create_acf_pacf_plots(df[value_col])
+
+        # Save processed data
+        processed_df.to_csv(os.path.join(app.config['UPLOAD_FOLDER'], 'processed_' + os.path.basename(filepath)))
+
+        return {
+            'plot_html': plot_html,
+            'forecast_html': forecast_html,
+            'acf_pacf_html': acf_pacf_html,
+            'summary': summary,
+            'filename': 'processed_' + os.path.basename(filepath),
+            'arima_params': arima_params,
+            'seasonal_params': seasonal_params,
+            'train_size': train_size,
+            'test_size': test_size
+        }
+
+    except Exception as e:
+        return {'error': str(e)}
+
+
+@app.route('/')
+def index():
+    return render_template('index.html')
+
+
+@app.route('/upload', methods=['POST'])
+def upload_file():
+    if 'file' not in request.files:
+        return render_template('index.html', error='No file part')
+
+    file = request.files['file']
+    if file.filename == '':
+        return render_template('index.html', error='No selected file')
+
+    if file and allowed_file(file.filename):
+        filename = secure_filename(file.filename)
+        filepath = os.path.join(app.config['UPLOAD_FOLDER'], filename)
+        file.save(filepath)
+        session['filepath'] = filepath  # Store filepath in session
+
+        # Get user selections
+        do_decomposition = 'decomposition' in request.form
+        do_forecasting = 'forecasting' in request.form
+        do_acf_pacf = 'acf_pacf' in request.form
+        train_percent = float(request.form.get('train_percent', 80)) / 100
+        test_percent = float(request.form.get('test_percent', 20)) / 100
+
+        # Validate train/test percentages
+        if abs(train_percent + test_percent - 1.0) > 0.01:  # Allow small float precision errors
+            return render_template('index.html', error='Train and test percentages must sum to 100%')
+
+        session['do_decomposition'] = do_decomposition
+        session['do_forecasting'] = do_forecasting
+        session['do_acf_pacf'] = do_acf_pacf
+
+        result = process_time_series(filepath, do_decomposition, do_forecasting, do_acf_pacf, train_percent,
+                                     forecast_periods=int(request.form.get('forecast_periods', 12)))
+
+        if 'error' in result:
+            return render_template('index.html', error=result['error'])
+
+        return render_template('results.html',
+                               do_decomposition=do_decomposition,
+                               do_forecasting=do_forecasting,
+                               do_acf_pacf=do_acf_pacf,
+                               train_percent=train_percent * 100,
+                               test_percent=test_percent * 100,
+                               forecast_periods=int(request.form.get('forecast_periods', 12)),
+                               **result)
+
+
+@app.route('/reforecast', methods=['POST'])
+def reforecast():
+    filepath = session.get('filepath')
+    if not filepath or not os.path.exists(filepath):
+        return render_template('index.html', error='Session expired or file not found. Please upload the file again.')
+
+    # Get user selections from reforecast form
+    train_percent = float(request.form.get('train_percent', 80)) / 100
+    test_percent = float(request.form.get('test_percent', 20)) / 100
+    forecast_periods = int(request.form.get('forecast_periods', 12))
+
+    # Validate train/test percentages
+    if abs(train_percent + test_percent - 1.0) > 0.01:  # Allow small float precision errors
+        return render_template('index.html', error='Train and test percentages must sum to 100%')
+
+    # Get original selections from session or defaults
+    do_decomposition = session.get('do_decomposition', False)
+    do_forecasting = True  # Since this is a reforecast
+    do_acf_pacf = session.get('do_acf_pacf', False)
+
+    result = process_time_series(filepath, do_decomposition, do_forecasting, do_acf_pacf, train_percent,
+                                 forecast_periods)
+
+    if 'error' in result:
+        return render_template('index.html', error=result['error'])
+
+    # Update session with new parameters
+    session['train_percent'] = train_percent
+    session['test_percent'] = test_percent
+    session['forecast_periods'] = forecast_periods
+
+    return render_template('results.html',
+                           do_decomposition=do_decomposition,
+                           do_forecasting=do_forecasting,
+                           do_acf_pacf=do_acf_pacf,
+                           train_percent=train_percent * 100,
+                           test_percent=test_percent * 100,
+                           forecast_periods=forecast_periods,
+                           **result)
+
+
+@app.route('/download/<filename>')
+def download_file(filename):
+    filepath = os.path.join(app.config['UPLOAD_FOLDER'], filename)
+    return send_file(filepath, as_attachment=True)
+
+
+if __name__ == '__main__':
+    app.run(debug=True)
\ No newline at end of file
diff --git a/templates/index.html b/templates/index.html
new file mode 100644
index 00000000..94543680
--- /dev/null
+++ b/templates/index.html
@@ -0,0 +1,76 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Time Series Analysis</title>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet">
+</head>
+<body>
+    <div class="container mt-5">
+        <h1 class="mb-4">Time Series Analysis App</h1>
+        <div class="card">
+            <div class="card-body">
+                <h5 class="card-title">Upload Time Series Data</h5>
+                <p class="card-text">Upload a CSV or Excel file with time series data. First column should be dates, second column should be values.</p>
+                <form method="post" enctype="multipart/form-data" action="/upload">
+                    <div class="mb-3">
+                        <input type="file" class="form-control" name="file" accept=".csv,.xls,.xlsx">
+                    </div>
+                    <h6 class="mt-3">Select Analyses:</h6>
+                    <div class="form-check">
+                        <input class="form-check-input" type="checkbox" name="decomposition" id="decomposition" checked>
+                        <label class="form-check-label" for="decomposition">
+                            Time Series Decomposition (Trend, Seasonality, Residuals)
+                        </label>
+                    </div>
+                    <div class="form-check">
+                        <input class="form-check-input" type="checkbox" name="forecasting" id="forecasting" checked>
+                        <label class="form-check-label" for="forecasting">
+                            Forecasting
+                        </label>
+                    </div>
+                    <div class="form-check">
+                        <input class="form-check-input" type="checkbox" name="acf_pacf" id="acf_pacf" checked>
+                        <label class="form-check-label" for="acf_pacf">
+                            ACF and PACF Plots
+                        </label>
+                    </div>
+                    <div class="mt-3" id="forecast_options" style="display: none;">
+                        <h6>Forecasting Options:</h6>
+                        <div class="mb-3">
+                            <label for="train_percent" class="form-label">Training Data Percentage (50-95%):</label>
+                            <input type="number" class="form-control" name="train_percent" id="train_percent" value="80" min="50" max="95" step="1">
+                        </div>
+                        <div class="mb-3">
+                            <label for="test_percent" class="form-label">Test Data Percentage (5-50%):</label>
+                            <input type="number" class="form-control" name="test_percent" id="test_percent" value="20" min="5" max="50" step="1">
+                        </div>
+                        <div class="mb-3">
+                            <label for="forecast_periods" class="form-label">Number of Periods to Forecast (1-24):</label>
+                            <input type="number" class="form-control" name="forecast_periods" id="forecast_periods" value="12" min="1" max="24" step="1">
+                        </div>
+                    </div>
+                    <button type="submit" class="btn btn-primary mt-3">Analyze</button>
+                </form>
+                {% if error %}
+                <div class="alert alert-danger mt-3">{{ error }}</div>
+                {% endif %}
+            </div>
+        </div>
+    </div>
+    <script>
+        // Show/hide forecasting options based on checkbox
+        document.getElementById('forecasting').addEventListener('change', function() {
+            document.getElementById('forecast_options').style.display = this.checked ? 'block' : 'none';
+        });
+        // Ensure train and test percentages sum to 100
+        const trainInput = document.getElementById('train_percent');
+        const testInput = document.getElementById('test_percent');
+        trainInput.addEventListener('input', function() {
+            testInput.value = (100 - parseFloat(this.value)).toFixed(0);
+        });
+        testInput.addEventListener('input', function() {
+            trainInput.value = (100 - parseFloat(this.value)).toFixed(0);
+        });
+    </script>
+</body>
+</html>
\ No newline at end of file
diff --git a/templates/results.html b/templates/results.html
new file mode 100644
index 00000000..44e0d571
--- /dev/null
+++ b/templates/results.html
@@ -0,0 +1,87 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Analysis Results</title>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet">
+    <script src="https://cdn.plot.ly/plotly-2.20.0.min.js"></script>
+</head>
+<body>
+    <div class="container mt-5">
+        <h1 class="mb-4">Time Series Analysis Results</h1>
+
+        <div class="card mb-4">
+            <div class="card-body">
+                <h5 class="card-title">Summary Statistics</h5>
+                <table class="table">
+                    {% for key, value in summary.items() %}
+                    <tr>
+                        <td>{{ key }}</td>
+                        <td>{{ value|round(2) }}</td>
+                    </tr>
+                    {% endfor %}
+                </table>
+            </div>
+        </div>
+
+        {% if do_decomposition %}
+        <div class="card mb-4">
+            <div class="card-body">
+                <h5 class="card-title">Time Series Decomposition</h5>
+                {{ plot_html | safe }}
+            </div>
+        </div>
+        {% endif %}
+
+        {% if do_forecasting %}
+        <div class="card mb-4">
+            <div class="card-body">
+                <h5 class="card-title">Forecast (ARIMA{{ arima_params }}, Seasonal{{ seasonal_params }})</h5>
+                <form method="post" action="/reforecast">
+                    <div class="mb-3">
+                        <label for="train_percent" class="form-label">Training Data Percentage (50-95%):</label>
+                        <input type="number" class="form-control" name="train_percent" id="train_percent" value="{{ train_percent }}" min="50" max="95" step="1">
+                    </div>
+                    <div class="mb-3">
+                        <label for="test_percent" class="form-label">Test Data Percentage (5-50%):</label>
+                        <input type="number" class="form-control" name="test_percent" id="test_percent" value="{{ test_percent }}" min="5" max="50" step="1">
+                    </div>
+                    <div class="mb-3">
+                        <label for="forecast_periods" class="form-label">Number of Periods to Forecast (1-24):</label>
+                        <input type="number" class="form-control" name="forecast_periods" id="forecast_periods" value="{{ forecast_periods }}" min="1" max="24" step="1">
+                    </div>
+                    <button type="submit" class="btn btn-primary">Re-run Forecast</button>
+                </form>
+                <hr>
+                <p>Training Data: {{ train_percent }}% ({{ train_size }} observations)</p>
+                <p>Test Data: {{ test_percent }}% ({{ test_size }} observations)</p>
+                <p>Forecast Periods: {{ forecast_periods }}</p>
+                {{ forecast_html | safe }}
+            </div>
+        </div>
+        {% endif %}
+
+        {% if do_acf_pacf %}
+        <div class="card mb-4">
+            <div class="card-body">
+                <h5 class="card-title">ACF and PACF Plots</h5>
+                {{ acf_pacf_html | safe }}
+            </div>
+        </div>
+        {% endif %}
+
+        <a href="/download/{{ filename }}" class="btn btn-primary">Download Processed Data</a>
+        <a href="/" class="btn btn-secondary">Upload Another File</a>
+    </div>
+    <script>
+        // Ensure train and test percentages sum to 100
+        const trainInput = document.getElementById('train_percent');
+        const testInput = document.getElementById('test_percent');
+        trainInput.addEventListener('input', function() {
+            testInput.value = (100 - parseFloat(this.value)).toFixed(0);
+        });
+        testInput.addEventListener('input', function() {
+            trainInput.value = (100 - parseFloat(this.value)).toFixed(0);
+        });
+    </script>
+</body>
+</html>
\ No newline at end of file
diff --git a/uploads/airline_passengers.csv b/uploads/airline_passengers.csv
new file mode 100644
index 00000000..e7eecfea
--- /dev/null
+++ b/uploads/airline_passengers.csv
@@ -0,0 +1,145 @@
+"Month","Thousands of Passengers"
+"1949-01",112
+"1949-02",118
+"1949-03",132
+"1949-04",129
+"1949-05",121
+"1949-06",135
+"1949-07",148
+"1949-08",148
+"1949-09",136
+"1949-10",119
+"1949-11",104
+"1949-12",118
+"1950-01",115
+"1950-02",126
+"1950-03",141
+"1950-04",135
+"1950-05",125
+"1950-06",149
+"1950-07",170
+"1950-08",170
+"1950-09",158
+"1950-10",133
+"1950-11",114
+"1950-12",140
+"1951-01",145
+"1951-02",150
+"1951-03",178
+"1951-04",163
+"1951-05",172
+"1951-06",178
+"1951-07",199
+"1951-08",199
+"1951-09",184
+"1951-10",162
+"1951-11",146
+"1951-12",166
+"1952-01",171
+"1952-02",180
+"1952-03",193
+"1952-04",181
+"1952-05",183
+"1952-06",218
+"1952-07",230
+"1952-08",242
+"1952-09",209
+"1952-10",191
+"1952-11",172
+"1952-12",194
+"1953-01",196
+"1953-02",196
+"1953-03",236
+"1953-04",235
+"1953-05",229
+"1953-06",243
+"1953-07",264
+"1953-08",272
+"1953-09",237
+"1953-10",211
+"1953-11",180
+"1953-12",201
+"1954-01",204
+"1954-02",188
+"1954-03",235
+"1954-04",227
+"1954-05",234
+"1954-06",264
+"1954-07",302
+"1954-08",293
+"1954-09",259
+"1954-10",229
+"1954-11",203
+"1954-12",229
+"1955-01",242
+"1955-02",233
+"1955-03",267
+"1955-04",269
+"1955-05",270
+"1955-06",315
+"1955-07",364
+"1955-08",347
+"1955-09",312
+"1955-10",274
+"1955-11",237
+"1955-12",278
+"1956-01",284
+"1956-02",277
+"1956-03",317
+"1956-04",313
+"1956-05",318
+"1956-06",374
+"1956-07",413
+"1956-08",405
+"1956-09",355
+"1956-10",306
+"1956-11",271
+"1956-12",306
+"1957-01",315
+"1957-02",301
+"1957-03",356
+"1957-04",348
+"1957-05",355
+"1957-06",422
+"1957-07",465
+"1957-08",467
+"1957-09",404
+"1957-10",347
+"1957-11",305
+"1957-12",336
+"1958-01",340
+"1958-02",318
+"1958-03",362
+"1958-04",348
+"1958-05",363
+"1958-06",435
+"1958-07",491
+"1958-08",505
+"1958-09",404
+"1958-10",359
+"1958-11",310
+"1958-12",337
+"1959-01",360
+"1959-02",342
+"1959-03",406
+"1959-04",396
+"1959-05",420
+"1959-06",472
+"1959-07",548
+"1959-08",559
+"1959-09",463
+"1959-10",407
+"1959-11",362
+"1959-12",405
+"1960-01",417
+"1960-02",391
+"1960-03",419
+"1960-04",461
+"1960-05",472
+"1960-06",535
+"1960-07",622
+"1960-08",606
+"1960-09",508
+"1960-10",461
+"1960-11",390
+"1960-12",432
\ No newline at end of file
diff --git a/uploads/processed_airline_passengers.csv b/uploads/processed_airline_passengers.csv
new file mode 100644
index 00000000..8361020e
--- /dev/null
+++ b/uploads/processed_airline_passengers.csv
@@ -0,0 +1,145 @@
+Month,Thousands of Passengers
+1949-01-01,112
+1949-02-01,118
+1949-03-01,132
+1949-04-01,129
+1949-05-01,121
+1949-06-01,135
+1949-07-01,148
+1949-08-01,148
+1949-09-01,136
+1949-10-01,119
+1949-11-01,104
+1949-12-01,118
+1950-01-01,115
+1950-02-01,126
+1950-03-01,141
+1950-04-01,135
+1950-05-01,125
+1950-06-01,149
+1950-07-01,170
+1950-08-01,170
+1950-09-01,158
+1950-10-01,133
+1950-11-01,114
+1950-12-01,140
+1951-01-01,145
+1951-02-01,150
+1951-03-01,178
+1951-04-01,163
+1951-05-01,172
+1951-06-01,178
+1951-07-01,199
+1951-08-01,199
+1951-09-01,184
+1951-10-01,162
+1951-11-01,146
+1951-12-01,166
+1952-01-01,171
+1952-02-01,180
+1952-03-01,193
+1952-04-01,181
+1952-05-01,183
+1952-06-01,218
+1952-07-01,230
+1952-08-01,242
+1952-09-01,209
+1952-10-01,191
+1952-11-01,172
+1952-12-01,194
+1953-01-01,196
+1953-02-01,196
+1953-03-01,236
+1953-04-01,235
+1953-05-01,229
+1953-06-01,243
+1953-07-01,264
+1953-08-01,272
+1953-09-01,237
+1953-10-01,211
+1953-11-01,180
+1953-12-01,201
+1954-01-01,204
+1954-02-01,188
+1954-03-01,235
+1954-04-01,227
+1954-05-01,234
+1954-06-01,264
+1954-07-01,302
+1954-08-01,293
+1954-09-01,259
+1954-10-01,229
+1954-11-01,203
+1954-12-01,229
+1955-01-01,242
+1955-02-01,233
+1955-03-01,267
+1955-04-01,269
+1955-05-01,270
+1955-06-01,315
+1955-07-01,364
+1955-08-01,347
+1955-09-01,312
+1955-10-01,274
+1955-11-01,237
+1955-12-01,278
+1956-01-01,284
+1956-02-01,277
+1956-03-01,317
+1956-04-01,313
+1956-05-01,318
+1956-06-01,374
+1956-07-01,413
+1956-08-01,405
+1956-09-01,355
+1956-10-01,306
+1956-11-01,271
+1956-12-01,306
+1957-01-01,315
+1957-02-01,301
+1957-03-01,356
+1957-04-01,348
+1957-05-01,355
+1957-06-01,422
+1957-07-01,465
+1957-08-01,467
+1957-09-01,404
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