Table:
|  |  | Three Months Ended |  |  |  |
| --- | --- | --- | --- | --- | --- |
|  | March 31, | June 30, | September 30, | December 31, | Year Ended December 31, |
| 2018: |  |  |  |  |  |
| Operating revenues | $1,741.8 | $1,780.9 | $1,785.5 | $2,131.9 | $7,440.1 |
| Costs of operations (1) | 519.9 | 560.3 | 556.7 | 540.9 | 2,177.8 |
| Operating income | 402.9 | 546.0 | 567.2 | 388.9 | 1,905.0 |
| Net income | 280.3 | 314.4 | 377.3 | 292.7 | 1,264.7 |
| Net income attributable to American Tower Corporation stockholders | 285.2 | 306.7 | 366.9 | 277.6 | 1,236.4 |
| Dividends on preferred stock | (9.4) | — | — | — | (9.4) |
| Net income attributable to American Tower Corporation common stockholders | 275.8 | 306.7 | 366.9 | 277.6 | 1,227.0 |
| Basic net income per share attributable to American Tower Corporation common stockholders | 0.63 | 0.69 | 0.83 | 0.63 | 2.79 |
| Diluted net income per share attributable to American Tower Corporation common stockholders | 0.63 | 0.69 | 0.83 | 0.62 | 2.77 |
Paragraphs:
AMERICAN TOWER CORPORATION AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Tabular amounts in millions, unless otherwise disclosed)
23. SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)
Selected quarterly financial data for the years ended December 31, 2019 and 2018 is as follows (in millions, except per share data):
(1) Represents Operating expenses, exclusive of Depreciation, amortization and accretion, Selling, general, administrative and development expense, and Other operating expenses.
Question:
What was the percentage change in operating revenues between Three Months Ended  September and December?
Answer: ($2131.9-$1785.5)/$1785.5 = 19.4