What is the change in current carrying amount of accounts receivable for 2018 to 2019?
{"Current": {"2018": 154607, "2019": 171866}, "Overdue <30 days": {"2018": 8802, "2019": 19977}, "Overdue 31-60 days": {"2018": 2258, "2019": 2076}, "Overdue 61-120 days": {"2018": 3507, "2019": 1599}, "Overdue >120 days": {"2018": 4276, "2019": 4017}, "Total": {"2018": 173450, "2019": 199535}}
current_2019 = df["Current"]["2019"]
current_2018 = df["Current"]["2018"]
answer = current_2019 - current_2018