pre_text: Unaudited Pro Forma Financial Information The pro forma financial information in the table below presents the combined results of operations for ACI and Speedpay as if the acquisition had occurred January 1, 2018. The pro forma information is shown for illustrative purposes only and is not necessarily indicative of future results of operations of the Company or results of operations of the Company that would have actually occurred had the transaction been in effect for the periods presented. This pro forma information is not intended to represent or be indicative of actual results had the acquisition occurred as of the beginning of each period, and does not reflect potential synergies, integration costs, or other such costs or savings. Certain pro forma adjustments have been made to net income (loss) for the year ended December 31, 2019 and 2018, to give effect to estimated adjustments that remove the amortization expense on eliminated Speedpay historical identifiable intangible assets, add amortization expense for the value of acquired identified intangible assets (primarily acquired software, customer relationships, and trademarks), and add estimated interest expense on the Company’s additional Delayed Draw Term Loan and Revolving Credit Facility borrowings. Additionally, certain transaction expenses that are a direct result of the acquisition have been excluded from the year ended December 31, 2019. The following is the unaudited summarized pro forma financial information for the periods presented (in thousands, except per share data): Walletron On May 9, 2019, the Company also completed the acquisition of Walletron, which delivers patented mobile wallet technology. The Company has included the financial results of Walletron in the consolidated financial statements from the date of acquisition, which were not material. RevChip and TranSend On October 1, 2019, the Company acquired certain technology assets of RevChip, LLC ("RevChip") and TranSend Integrated Technologies Inc. ("TranSend") for a combined $7.0 million. As substantially all of the value was in the developed technology, the purchase was recognized as an asset acquisition. The Company has included the financial results of RevChip and TranSend in the consolidated financial statements from the date of acquisition, which were not material.
table: Years Ended December 31,
table: 2019 2018
table: Pro forma revenue $1,382,957 $1,361,729
table: Pro forma net income $82,003 $88,428
table: Pro forma income per share:
table: Basic $ 0.71 $ 0.76
table: Diluted $ 0.69 $ 0.75
question: Analyse this data from a financial earnings document. What was the change in pro forma revenue between 2018 and 2019?