Table:
|  | December 31, |  |
| --- | --- | --- |
| (In millions) | 2019 | 2018 |
| Balance at beginning of period(1) | $ 150.1 | $ 71.5 |
| Gains (losses) on assets still held at end of year | 16.8 | (16.0) |
| Purchases, sales, issuance, and settlements(2) | 8.3 | 103.7 |
| Transfers in and/or out of Level 3 | — | 1.0 |
| Foreign exchange gain (loss) | 5.0 | (10.1) |
| Balance at end of period(1) | $ 180.2 | $ 150.1 |
Paragraphs:
The following table shows the activity of our U.S. and international plan assets, which are measured at fair value using Level 3 inputs.
(1) Balances as of December 31, 2018 have been revised from our 2018 Form 10-K filing to reflect changes in leveling classification of specific funds. These reclassifications did not impact the fair value of any of our pension plan assets.
(2) Purchases of Level 3 assets in 2018 primarily represent the purchase of bulk annuity contracts (buy-ins) in some of our international plans.
Question:
What is the difference between the Balance at end of period for 2018 and 2019?
Answer: 180.2-150.1 = 30.1