It might be depending on multiple factors, smart home size, apps, devices etc…
Anyway, odd is that I have some peaks as well (1min,5min and 15min average), since the beginning…
If you have mostly Advanced flows, you might analyse what flows is doing implementing Simplelog logging… [APP][Pro] Simple (Sys) LOG - Use this app for Simple (Sys) Logging - the script unfortunately does support only Advanced flows currently.