How do you calculate the average purchase value?

APV $=($Number of Transactions$)-$: $($Number of Purchases$)$

APV $=($Total Revenue$)-$: $($Number of Transactions$)$

APV $=($Average Purchase Value$)\backslash$times $($Purchases in a Single Year$)\backslash$times $($Average Number of Years Retained$)$

APV $=($Average Purchase Value$)\backslash$times $($Total Revenue$)$