Split balance amount between statements

InstallmentBalanceSplit.php

    public function calculateInstallmentAmounts(
        int $installments,
        string $description,
        float $amount
    ): Collection {
        $diff_sum = (round((pow(10, 2) * $amount)) % $installments) / pow(10, 2);
        $installment_amount = ($amount - $diff_sum) / $installments;
        $installment = array_fill(1, $installments, [$description => $installment_amount]);

        return $this->distributeBalanceBetweenInstallments($diff_sum, $installment, $description, $installments);
    }

    private function distributeBalanceBetweenInstallments(
        float $diff_sum,
        array $installment,
        string $description,
        int $installments
    ): Collection {
        $idx = 1;
        for ($i = $diff_sum * 100; $i > 0; $i--) {
            $installment[$idx++][$description] += 0.01;
            $idx = ($idx > $installments) ? 1 : $idx;
        }

        return collect($installment);
    }