Table:
|  |  | As of December 31, 2019 |  |  |
| --- | --- | --- | --- | --- |
|  | Amortized | Unrealized | Unrealized | Fair |
|  | Cost | Gains | Losses | Value |
| Foreign government obligations | $129,499 | $— | $3,433 | $126,066 |
| U.S. government obligations | 99,700 | — | 1,981 | 97,719 |
| Total . | $229,199 | $— | $5,414 | $223,785 |
|  |  | As of December 31, 2018 |  |  |
|  | Amortized | Unrealized | Unrealized | Fair |
|  | Cost | Gains | Losses | Value |
| Foreign government obligations | $73,798 | $14,234 | $235 | $87,797 |
| U.S. government obligations | 97,223 | 416 | 6,436 | 91,203 |
| Total | $171,021 | $14,650 | $6,671 | $179,000 |
Paragraphs:
The following tables summarize the unrealized gains and losses related to our restricted investments, by major security type, as of December 31, 2019 and 2018 (in thousands):
As of December 31, 2019, we had no restricted investments in a loss position for a period of time greater than 12 months. As of December 31, 2018, we identified six restricted investments totaling $87.4 million that had been in a loss position for a period of time greater than 12 months with unrealized losses of $6.4 million. The unrealized losses were primarily due to increases in interest rates relative to rates at the time of purchase. Based on the underlying credit quality of the investments, we generally hold such securities until we recover our cost basis. Therefore, we did not consider these securities to be other-than-temporarily impaired.
Question:
What was the reason for the unrealized losses in 2018?
Answer: The unrealized losses were primarily due to increases in interest rates relative to rates at the time of purchase.