Add arg to `allowance()` whether or not to round return value to nearest £10

[Mark-Eis]

Fiscal/R/allowance.R

Line 2 in e22ac22

function(taxable, deficit = NULL, opts = tax_opts()) {

function(taxable, deficit = NULL, round10 = TRUE, opts = tax_opts()) {

Fiscal/R/allowance.R

Line 18 in e22ac22

allow - max(min(((sum(band) + 1 - taxable) / 2 + 9), offset), 0) # adjustment as for incometax()

    with(opts,
        {
            ...
            allow <- allow - max(min(((sum(band) + 1 - taxable) / 2 + 9), offset), 0)        # adjustment as for incometax()     
            if (round10) round(allow, -1) else allow 
        }
    )

[Mark-Eis]

Must always round down using {base} floor() so if anything, tax is slightly overpaid, not underpaid.

[Mark-Eis]

a4c3abd