Subject: mathqa
Question: a broker invested her own money in the stock market . during the first year , she increased her stock market wealth by 40 percent . in the second year , largely as a result of a slump in the stock market , she suffered a 30 percent decrease in the value of her stock investments . what was the net increase or decrease on her overall stock investment wealth by the end of the second year ?
Option: 
A: 15 %
B: 20 %
C: 80 %
D: − 2 %
Answer: D