Table:
Years Ended December 31,

2019	2018	2017

Number of shares of common stock granted	16	16	13

Weighted average grant-date fair value per common stock	$29.10	$28.48	$30.49

Fair value of common stock vested	$320	$315	$334

Cash used to settle the obligation	$366	$804	$1,134

Answer the following question based on both the table and the accompanying text, produce your answer and, if helpful, briefly explain your calculation. Conclude with JSON: {"answer": ["ANSWER"], "scale": "SCALE"} ("scale" = "" if no unit).

Context:
The following table summarizes information regarding shares of common stock granted and vested (in thousands, except per common stock amounts):
As of December 31, 2019, there was $0.2 million of total unrecognized compensation cost, net of actual forfeitures, related to nonvested common stock. This cost is expected to be recognized over a weighted average period of 4.2 years.

Question: What was the percentage change in Fair value of common stock vested in 2019 from 2018?

(($320-$315)/$315) * 100, therefore {"answer": "1.59", "scale": "percent"}