cara menghitung persentase di laravel berdasarkan bulan gmn?

jadi saya punya controller seperti ini

$bruto_l_b = DB::table('bruto_l_b')->where('date', [$tglawal])->sum('nominal');
$pokok_l_b = DB::table('pokok_l_b')->where('date', [$tglawal])->sum('hutang_pokok');
$bunga_l_b = DB::table('bunga_l_b')->where('date', [$tglawal])->sum('bunga');

nah kodingan persentase nya gmn ya gan?

kan klo di sql script nya kyk gini gan tp ini tanpa berdasarkan bulan

SELECT  SUM(COALESCE(nominal,0)/(COALESCE(nominal,0)
+COALESCE(hutang_pokok,0)+COALESCE(bunga_l_b,0)
+COALESCE(macet,0)))*100 AS persentase
FROM bruto_l_b, pokok_l_b, bunga_l_b;