Table:
|  | Year Ended December 31, |  |
| --- | --- | --- |
|  | 2019 | 2018 |
| Pro forma revenues | $7,904.2 | $7,936.0 |
| Pro forma net income attributable to American Tower Corporation common stockholders | $1,844.9 | $1,122.6 |
| Pro forma net income per common share amounts: |  |  |
| Basic net income attributable to American Tower Corporation common stockholders | $4.17 | $2.55 |
| Diluted net income attributable to American Tower Corporation common stockholders | $4.14 | $2.53 |
Paragraphs:
AMERICAN TOWER CORPORATION AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Tabular amounts in millions, unless otherwise disclosed)
2018 Transactions
During the year ended December 31, 2019, the allocation of the final purchase price for the acquisition of Idea Cellular Infrastructure Services Limited was finalized with no material post-closing adjustments. During the year ended December 31, 2019, there were no material post-closing adjustments that impacted other 2018 acquisitions.
Pro Forma Consolidated Results (Unaudited)
The following table presents the unaudited pro forma financial results as if the 2019 acquisitions had occurred on January 1, 2018 and the 2018 acquisitions had occurred on January 1, 2017. The pro forma results do not include any anticipated cost synergies, costs or other integration impacts. Accordingly, such pro forma amounts are not necessarily indicative of the results that actually would have occurred had the transactions been completed on the dates indicated, nor are they indicative of the future operating results of the Company.
Question:
What was the change in the Diluted net income attributable to American Tower Corporation common stockholders between 2018 and 2019?