b.Actual sales for October and November and expected sales for December are as follows:

October November December Cash sales $65,000 $70,000 $83,000 Sales on account $400,000 $525,000 $600,000

Sales on account are collected over a three-month period as follows: 20% collected in the month of sale, 60% collected in the month following sale, and 18% collected in the second month following sale. The remaining 2% is uncollectible.

Prepare a schedule of expected cash collections for December. (Omit the "$" sign in your response.) December cash sales $ 83,000 Collections on account: October sales November sales December sales

Ok, to get collections on account for November sales, we do 525,000 x 60%

to get collections on account for October, we do 400,000 x 20%

My question is, isn't the following month for December a January? and second month following sale is Febuary.. I really don't understand why we calculate to the past months? Any good explanation for this?