Course 4 - ASM Question

[Alien]

Does anybody know why r_sub_T equals to 536 minus 504 on Problem 36.16 on page 191 of the ASM Course 4? Thanks

[New at pd]

Does anybody know why r_sub_T equals to 536 minus 504 on Problem 36.16 on page 191 of the ASM Course 4? Thanks

What is the question?

[phdmom]

The l-period forecast is y_(t+l) = y_t + l* r_t. So, y_(t+1) - y_t = r_t.