Table:
0
A
B
C
D
1
Years Ended December 31,
2
2019
2018
2017
3
Expected life (years)
2.8
2.9
2.9
4
Interest rate
2.5%
2.4%
1.5%
5
Volatility
29.3%
28.0%
26.5%
6
Expected dividend yield
—
—
—

Questions and formulas:
Question: What was the change in interest rate between 2018 and 2019?
Formula: B4-C4
Formula2: B4-C4
Level: Calculation
Question: What was the change in Volatility between 2017 and 2018?
Formula: C5-D5
Formula2: C5-D5
Level: Calculation
Question: What was the percentage change in expected life (years) between 2018 and 2019?
Formula: (B3-C3)/C3
Formula2: (B3-C3)/C3
Level: Calculation