where $n$ is the number of years of useful life of the asset.

$SYD=\frac{n(n+1)}{2}$

The sum$-$of$-$the$-$years' digits depreciation rate fraction can be expressed as follows.

$SYD$ depreciation rate fraction $=\frac{\text{y}\text{e}\text{a}\text{r}\text{s}of\text{u}\text{s}\text{e}\text{f}\text{u}\text{l}\text{l}\text{i}\text{f}\text{e}\text{r}\text{e}\text{m}\text{a}\text{i}\text{n}\text{i}\text{n}\text{g}}{SYD}$

There are $n=7$ years of useful life for the wood pulp mixer. Find SYD$.$

$SYD=\frac{n(n+1)}{2}$

$=\frac{7(7+1)}{2}$

$=$

and so on$.$ Complete the table of depreciation rate fractions.

$\backslash$table$[[$Year$,\backslash$table$[[$Depreciation$],[$Rate$],[$Fraction$]],],[1,\backslash$table$[[$years of useful life remaining $=$