Analisis penerapan Cadangan Kerugian Kredit Ekspektasian (CKKE) berdasarkan PSAK 71 terhadap piutang imbal jasa penjaminan KUR: studi kasus pada PT Jaminan Kredit Indonesia = Analysis of the implementation of allowance of expected credit loss based on PSAK 71 against KUR guarantee services receivables: a case study at PT Jaminan Kredit Indonesia