Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Calculation/Statistical.php
public static function VARFunc(...$args)
    {
        $returnValue = Functions::DIV0();

        $summerA = $summerB = 0;

        // Loop through arguments
        $aArgs = Functions::flattenArray($args);
        $aCount = 0;
        foreach ($aArgs as $arg) {
            if (is_bool($arg)) {
                $arg = (int) $arg;
            }
            // Is it a numeric value?
            if ((is_numeric($arg)) && (!is_string($arg))) {
                $summerA += ($arg * $arg);
                $summerB += $arg;
                ++$aCount;
            }
        }

        if ($aCount > 1) {
            $summerA *= $aCount;
            $summerB *= $summerB;
            $returnValue = ($summerA - $summerB) / ($aCount * ($aCount - 1));
        }

        return $returnValue;
    }
public static function VARFunc(...$args)
    {
        $returnValue = Functions::DIV0();

        $summerA = $summerB = 0;

        // Loop through arguments
        $aArgs = Functions::flattenArray($args);
        $aCount = 0;
        foreach ($aArgs as $arg) {
            if (is_bool($arg)) {
                $arg = (int) $arg;
            }
            // Is it a numeric value?
            if ((is_numeric($arg)) && (!is_string($arg))) {
                $summerA += ($arg * $arg);
                $summerB += $arg;
                ++$aCount;
            }
        }

        if ($aCount > 1) {
            $summerA *= $aCount;
            $summerB *= $summerB;
            $returnValue = ($summerA - $summerB) / ($aCount * ($aCount - 1));
        }

        return $returnValue;
    }
VARFunc.

Estimates variance based on a sample.

Excel Function:
VAR(value1[,value2[, ...]])

@category Statistical Functions

@param mixed ...$args Data values

@return float