dec

Enables the use of the unary -- operator for BigDecimal instances.

inline operator fun BigDecimal.dec(): BigDecimal(source)

import java.math.BigDecimal

fun main() {
    var amount = BigDecimal("100.00")
    println("Before decrement: $amount")   // 100.00
    amount--
    println("After decrement:  $amount")   // 99.00
}

Source