Consider the following graph and the 7th and 8th statements.
For me, the 7th and 8th statements are ambiguous.
If we consider the statement only by subtracting 13.2 from 18.9 which is 5.7 then the statement is true.
But if we calculate the percentage of increment by (18.9-13.2)/13.2 = 0.43 then the statement is false.
If we consider the statement only by comparing 2 consecutive years then the statement is true.
However, if comparison can be performed on any pairs then the statement will be false because the most decrements occur between 1965 and 2001.
Do you think these 2 statements ambiguous? Or there are some conventions among Japanese that I miss here.