What is the percentage change in stock-based compensation expense from 2017 to 2018?
{"Stock-based compensation expense by caption -- Cost of goods sold": {"2019": 102, "2018": 83, "2017": 88}, "Stock-based compensation expense by caption -- Selling, general, and administrative": {"2019": 73, "2018": 61, "2017": 75}, "Stock-based compensation expense by caption -- Research and development": {"2019": 68, "2018": 54, "2017": 52}, "Stock-based compensation expense by caption -- ": {"2019": 243, "2018": 198, "2017": 215}, "Stock-based compensation expense by type of award -- Restricted stock awards": {"2019": 178, "2018": 140, "2017": 144}, "Stock-based compensation expense by type of award -- Stock options": {"2019": 33, "2018": 55, "2017": 71}, "Stock-based compensation expense by type of award -- ESPP": {"2019": 32, "2018": 3, "2017": "\u2014"}, "Stock-based compensation expense by type of award -- ": {"2019": 243, "2018": 198, "2017": 215}}
stock_compensation_2018 = df["Stock-based compensation expense by caption -- "]["2018"]
stock_compensation_2017 = df["Stock-based compensation expense by caption -- "]["2017"]
answer = (stock_compensation_2018 - stock_compensation_2017) / stock_compensation_2017 * 100.0