Non cash consideration – revenue

For non cash consideration

Quesrion :
Dan sells a good to Stan, control over the good is transferred on 1 jan 20×1. The consideration received by Dan is 1000shares in Stan with a fair value of $4 each. By 31 dec 20×1, the shares in Stan have a fair value of $5 each

Required :
How much revenue shd be recognized from this trx in the financial statements if Dan for the year ended 31 dec 20×1

For the answer, y do we use $4, not $5?? Cuz the q is asking 31 dec 20xq so dont we have to use 4 like the date of financialstatement ended???