Larry Jenkin$$ at CFC manufacturing is developing a forecast demand using the simple moving average. If Larry uses four prior yearly sales values $($i$.$e$.,$ year $1=100,$ year $2=120,$ year $3=140,$ and year $4=210),$ which of the following is the simple moving average forecast in the fifth year?

$103\mathrm{.}5$

$131\mathrm{.}0$

$142\mathrm{.}5$

$147\mathrm{.}5$

$156\mathrm{.}0$