pre_text: Financing and cash flow The Group delivered very strong cash generation in 2019, driven by higher operating profit and effective working capital management. Changes in working capital, reflected within cash flow from operations, benefited from: • our continued focus on improving trade receivables collection; • a reduction in inventory levels due to a high level of shipments at the end of 2019; and • growth in payables, resulting from the increase in activity levels and emphasis on extending supplier payment terms. Free cash flow for 2019 almost doubled year-on-year coming in at $100.1 million, compared to $50.9 million in 2018, resulting in a free cash flow conversion which represented 123 per cent of adjusted earnings (2018 77 per cent). Free cash flow is set out below: Note 1. Spirent adopted IFRS 16 on 1 January 2019; in prior periods operating lease payments were included within cash flow from operations. Free cash flow includes a net cash outflow in respect of exceptional items in 2018 and 2019 of $5.5 million (2018 $3.6 million in respect of exceptional items charged in 2017 and 2018). Tax payments of $5.6 million made in 2019 were consistent with the prior year (2018 $5.7 million). Net capital expenditure of $11.9 million was also broadly consistent with the prior year (2018 $10.6 million), with the incremental spend of $1.3 million primarily related to investment in 5G. We continue to exercise careful management of capital investment to ensure efficient use of capital and maximise return on investment. Following the adoption of IFRS 16 on 1 January 2019, the payment of lease liabilities, both the principal and interest elements, are shown separately from net cash flow from operating activities. In previous periods they would have been reflected in that number. There is no overall impact in comparing free cash flow year-on-year. In 2019, the final dividend for 2018 and an interim dividend for 2019 totalling $28.6 million were paid. This compared to total dividends of $54.8 million paid in 2018, including a special dividend of $29.9 million. In addition, 4.0 million shares were purchased and placed into the Employee Share Ownership Trust at a cost of $8.6 million (2018 1.5 million shares at a net cost of $2.5 million) and $1.9 million of cash consideration was paid to acquire the business of a navigation systems company based in the United Kingdom. Following these payments, cash and cash equivalents closed at $183.2 million at 31 December 2019, compared with $121.6 million at 31 December 2018. There continues to be no bank debt.
table: $ million 2019 2018
table: Cash flow from operations 124.9 65.9
table: Tax paid (5.6) (5.7)
table: Net cash inflow from operating activities 119.3 60.2
table: Interest received 2.6 1.3
table: Net capital expenditure (11.9) (10.6)
table: Payment of lease liabilities, principal and interest1 (10.3) —
table: Lease payments received from finance leases 0.4 —
table: Free cash flow 100.1 50.9
question: Analyse this data from a financial earnings document. What was the change in free cash flow?