Regulation (EU) 2016/867 defines cumulative recoveries as:

the total amount recovered since the date of default.

It is further described in the AnaCredit Module Part II as:

the amount received from the start of the latest default of the instrument until the reporting reference date. For the purpose of this attribute, a ‘default’ will be deemed to have occurred if it meets the conditions of Article 178 of Regulation (EU) No 575/2013.

The minimum amount recorded should be 0.