Cumulative Discount Factor
(CDF or CumDF).
The Cumulative Discount Factor (CDF) is quoted for a defined number of periods, for example 10.
The CDF is the total of all of the individual discount factors, up to and including the last maturity (10 in this case).
When the periodic yield is equal for all the maturities in question, the CDF is the same as the annuity factor (AF).