Update app.py

app.py

@@ -61,19 +61,42 @@ If I had more time, I would have enhanced the visualisation by adding interactiv
 
 
 # Visualization 2: Line chart showing licenses issued over time
+# st.subheader("Licenses Over Time")
+# time_data = df.groupby('Original Issue Year').size().reset_index(name='License Count')
+
+# if not time_data.empty:
+#     chart2 = alt.Chart(time_data).mark_line().encode(
+#         x=alt.X('Original Issue Year', title='Year'),
+#         y=alt.Y('License Count', title='Number of Licenses'),
+#         color=alt.value('blue')
+#     ).properties(
+#         width=600,
+#         height=400,
+#         title="Number of Licenses Issued Over Time"
+#     )
+#     st.altair_chart(chart2)
+# else:
+#     st.write("No data available for the 'Licenses Over Time' plot.")
+
 st.subheader("Licenses Over Time")
+
 time_data = df.groupby('Original Issue Year').size().reset_index(name='License Count')
 
 if not time_data.empty:
-    chart2 = alt.Chart(time_data).mark_line().encode(
-        x=alt.X('Original Issue Year', title='Year'),
-        y=alt.Y('License Count', title='Number of Licenses'),
+    chart2 = alt.Chart(time_data).mark_line(point=True).encode(
+        x=alt.X('Original Issue Year:O', title='Year'),  # Ordinal scale for better control
+        y=alt.Y('License Count:Q', title='Number of Licenses'),
+        tooltip=[
+            alt.Tooltip('Original Issue Year:O', title='Year'),
+            alt.Tooltip('License Count:Q', title='Number of Licenses')
+        ],
         color=alt.value('blue')
     ).properties(
         width=600,
         height=400,
         title="Number of Licenses Issued Over Time"
-    )
+    ).interactive()  # Enables zooming and panning
+
     st.altair_chart(chart2)
 else:
     st.write("No data available for the 'Licenses Over Time' plot.")