Quant Q

I thought this question was really simple but got it wrong… I think I’m missing something… suggestions? Consider the following estimated model: (Salest - Sales t-1) = 30 + 1.25 (Sales t-1 - Sales t-2) + 1.1 (Sales t-4 - Sales t-5) t=1,2,… T and Sales for the periods 1999.1 through 2000.2: t Period Sales T 2000.2 $2,000 T-1 2000.1 $1,800 T-2 1999.4 $1,500 T-3 1999.3 $1,400 T-4 1999.2 $1,900 T-5 1999.1 $1,700 The forecasted Sales amount for 2000.3 is closest to: A) $2,270. B) $270. C)$1,730. D)$2,625.

(Salest - Sales t-1) = 30 + 1.25 (Sales t-1 - Sales t-2) + 1.1 (Sales t-4 - Sales t-5) (SALES-2000.3 - 2000) = 30 + 1.25*(2000 - 1800) + 1.1*(1400-1900) SALES-2000.3 -2000 = 30 + 250 -550 SALES-2000.3 = 1730 = C?

Correct! I actually just got it. Complete oversight of the 2000.3… Thanks for your reply!