Table:
|  | 2019 | 2018 | 2017 |
| --- | --- | --- | --- |
| Gross amount of accumulated depreciation at beginning | $(5,724.7) | $(5,181.2) | $(4,548.1) |
| Additions during period: |  |  |  |
| Depreciation | (768.4) | (751.4) | (718.7) |
| Other | — | — | — |
| Total additions | (768.4) | (751.4) | (718.7) |
| Deductions during period: |  |  |  |
| Amount of accumulated depreciation for assets sold or disposed | 121.4 | 129.3 | 100.7 |
| Other (7) | (10.5) | 78.6 | (15.1) |
| Total deductions | 110.9 | 207.9 | 85.6 |
| Balance at end | $(6,382.2) | $(5,724.7) | $(5,181.2) |
Paragraphs:
AMERICAN TOWER CORPORATION AND SUBSIDIARIES SCHEDULE III—SCHEDULE OF REAL ESTATE AND ACCUMULATED DEPRECIATION (dollars in millions)
(7) Primarily includes foreign currency exchange rate fluctuations and other deductions.
Question:
What was the change in Gross amount of accumulated depreciation at beginning between 2017 and 2018?
Answer: -$5181.2-(-$4548.1) = -633.1