The provided pie charts illustrate sharply the proportion of three different kinds of 
books
 sold by a bookseller between 1972 and 2012.
At first glance, it is apparent that almost Use synonyms
types
 of Correct determiner usage
all types
books
 increased in sales over the given period, including adult Use synonyms
fiction
, children’s Use synonyms
fiction
 and travel Use synonyms
books
. Meanwhile, biography Use synonyms
books
 tended to decrease Use synonyms
year-by-year
.
Focusing originally on the first chart, it can be obviously perceived that in 1972 the share of three Correct your spelling
year by year
books
, including adult Use synonyms
fiction
, children’s Use synonyms
fiction
, and biography Use synonyms
books
, each of them accounted for 20%. Use synonyms
While
, the number of travel Linking Words
books
 was only 15%, and the remaining 25% belonged to other types of Use synonyms
books
.
In the 1992 chart, the figure Use synonyms
of
 almost Change preposition
for
kinds
 of Correct determiner usage
all kinds
books
 tended to rise slightly, except Use synonyms
biography
 Change preposition
for biography
books
. Use synonyms
Finally
, in 2012, the ratio of adult and children Linking Words
fiction
 skyrocketed, in which the former made up nearly Use synonyms
a 
half, and the latter was a quarter. Meanwhile, the percentage of other types of Correct article usage
apply
books
 occupied an insignificant part.Use synonyms