Added statistics model, updated revenue model

models/core/dm_monthly_zone_statistics.sql

@@ -0,0 +1,21 @@
+{{ config(materialized='table') }}
+
+with trips_data as (
+select * from {{ ref('fact_trips') }}
+)
+select
+-- Reveneue grouping
+pickup_zone as revenue_zone,
+date_trunc('month', pickup_datetime) as revenue_month,
+--Note: For BQ use instead: date_trunc(pickup_datetime, month) as revenue_month,
+
+service_type,
+
+-- Additional calculations
+count(tripid) as total_monthly_trips,
+avg(passenger_count) as avg_montly_passenger_count,
+avg(trip_distance) as avg_montly_trip_distance
+
+from trips_data
+group by 1,2,3
+