reading 18 example 7 question 2

question states…

“this cost is expected to be recognized over a weighted average period of 1.7 years”

solution states…

“the options will be granted to vest over the next 1.7 years”

I would say a weighted average of 1.7 years means that (assuming costs are flat) then 3.4 years is the period to spead costs over.

year 1 = $197

year 2 = $138

does not give an average of 1.7 years, but something closer to 10 months. anyone want to correct me?