question:
What is our ARR by product line and how has the mix shifted?

datasets:
- incidentio_subscriptions.csv (136 rows): Subscription records with subscription_id, customer_id, sku_code, mrr_local, mrr_local_reported, fx_to_usd, status, period_end, seats, tier
- incidentio_customers.csv (85 rows): Customer master with customer_id, customer_name, region, signup_date, industry
- incidentio_skus.csv (8 rows): SKU mapping with sku_code, product_line, launch_date, pricing_model

expected answer:
ARR by product line (Q4 2025, period_end = 2025-12-31): Total ARR $47.7M. On-Call: $20.0M (42%), Incident Response: $23.4M (49%), Status Pages: $4.3M (9%). Note: ARR = (mrr_local * fx_to_usd) * 12 for active subscriptions only. Join subscriptions→skus on sku_code to map product_line.

Mix shift (Q4 2024 → Q4 2025): On-Call share increased from 10.8% to 42.0%. Incident Response share decreased from 75.4% to 49.0%. Status Pages share decreased from 13.8% to 9.0%. On-Call YoY growth of 432%.

QoQ growth by product line (2025): Q2: On-Call 38.9%, IR 2.3%, Status 1.2%. Q3: On-Call 37.6%, IR 1.8%, Status 1.7%. Q4: On-Call 16.5%, IR 2.1%, Status 1.7%.

Crossover projection: At current QoQ rates (Q3→Q4 2025), On-Call surpasses Incident Response in Q2 2026 (2026-06-30) with projected On-Call $27.2M vs IR $24.3M.

Products launched in last 18 months: Using cutoff date 2024-06-30, 44.2% of ARR comes from products launched since that date.
