What is the percentage change in the trade receivables from 2018 to 2019?
{"Trade receivables": {"2019 $000": 6165, "2018 $000": 4952}, "Allowance for credit losses": {"2019 $000": "-", "2018 $000": -15}, "Contract assets": {"2019 $000": 16824, "2018 $000": 23773}, "": {"2019 $000": 22989, "2018 $000": 28710}, "The ageing analysis of trade rec The ageing analysis of trade receivables is as follows: -- Current": {"2019 $000": 4967, "2018 $000": 4408}, "The ageing analysis of trade rec The ageing analysis of trade receivables is as follows: -- Past due 1  30 days": {"2019 $000": 1024, "2018 $000": 291}, "The ageing analysis of trade rec The ageing analysis of trade receivables is as follows: -- Past due 31  90 days": {"2019 $000": 130, "2018 $000": 108}, "The ageing analysis of trade rec The ageing analysis of trade receivables is as follows: -- Past due 90+ days": {"2019 $000": 44, "2018 $000": 130}, "The ageing analysis of trade rec The ageing analysis of trade receivables is as follows: -- ": {"2019 $000": 6165, "2018 $000": 4937}}
trade_receivables_2019 = df["Trade receivables"]["2019 $000"]
trade_receivables_2018 = df["Trade receivables"]["2018 $000"]
answer = ( trade_receivables_2019 - trade_receivables_2018 ) / trade_receivables_2018 * 100.0