Table:
|  | 2019 | 2018 |
| --- | --- | --- |
| Beginning balance as of January 1, | $1,210.0 | $1,175.3 |
| Additions | 61.8 | 39.6 |
| Accretion expense | 81.6 | 83.6 |
| Revisions in estimates (1) | 56.8 | (81.5) |
| Settlements | (26.1) | (7.0) |
| Balance as of December 31, | $1,384.1 | $1,210.0 |
Paragraphs:
AMERICAN TOWER CORPORATION AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENT(Tabular amounts in millions, unless otherwise disclosed)
11. ASSET RETIREMENT OBLIGATIONS
The changes in the carrying amount of the Company’s asset retirement obligations were as follows:
(1) Revisions in estimates include decreases to the liability of $6.7 million and $49.4 million related to foreign currency translation for the years ended December 31, 2019 and 2018, respectively.
As of December 31, 2019, the estimated undiscounted future cash outlay for asset retirement obligations was $3.2 billion.
Question:
What was the change in balance as of December 31 between 2018 and 2019?
Answer: $1384.1-$1210.0 = 174.1