Net New recurring revenue (ARR or MRR) is the change in recurring revenue from one period to the next. Therefore:
Net New = New Sales + Resurrection + Expansion - Contraction - Churn
Net New ARR is the best metric for understanding ARR trajectory. If Net New ARR is steadily increasing each quarter than the company is accelerating and a high growth rate can likely be sustained. However, flat Net New ARR is an early indicator that growth is starting to decline. While year over year growth might still look good, if Net New ARR is flat the growth rate with start to drop quickly.