How to Calculate the Percentage through the Tax Year in PHP

Recently a client requested that we display for them a percentage of how far through the tax year we are. I did some looking online however I couldn’t find anything which suited my needs.

Below is the code I ended up writing which will calculate the percentage value and display the output at the end.

$currentMonth     = date('n');

$currentYear      = date('Y');

$dayInYear        = date('z');

$taxYearStartYear = $currentMonth < 4 ? $currentYear - 1 : $currentYear;

$taxYearStart     = $taxYearStartYear . '-04-01 00:00:00';

$taxYearStartDay  = date('z', strtotime($taxYearStart));

$taxDayInYear     = $dayInYear < $taxYearStartDay ? ($dayInYear + 365) - $taxYearStartDay : $dayInYear - $taxYearStartDay;

$taxYearPassed    = ($taxDayInYear / 365) * 100;

echo $taxYearPassed.'% of the way through the tax year';