(excerpted and quoted with adaptation from About Google Ngram Viewer)
+ | sums the expressions on either side, letting you combine multiple ngram time series into one. |
- | subtracts the expression on the right from the expression on the left, giving you a way to measure one ngram relative to another. Because users often want to search for hyphenated phrases, put spaces on either side of the - sign. |
/ | divides the expression on the left by the expression on the right, which is useful for isolating the behavior of an ngram with respect to another. |
* | multiplies the expression on the left by the number on the right, making it easier to compare ngrams of very different frequencies. (Be sure to enclose the entire ngram in parentheses so that * isn't interpreted as a wildcard.) |
: | applies the ngram on the left to the corpus on the right, allowing you to compare ngrams across different corpora. |
Informal corpus name | Shorthand | Persistent identifier | Description |
American English 2012 | eng_us_2012 | googlebooks-eng-us-all-20120701 | Books predominantly in the English language that were published in the United States. |
American English 2009 | eng_us_2009 | googlebooks-eng-us-all-20090715 | |
British English 2012 | eng_gb_2012 | googlebooks-eng-gb-all-20120701 | Books predominantly in the English language that were published in Great Britain. |
British English 2009 | eng_gb_2009 | googlebooks-eng-gb-all-20090715 | |
Chinese 2012 | chi_sim_2012 | googlebooks-chi-sim-all-20120701 | Books predominantly in simplified Chinese script. |
Chinese 2009 | chi_sim_2009 | googlebooks-chi-sim-all-20090715 | |
English 2012 | eng_2012 | googlebooks-eng-all-20120701 | Books predominantly in the English language published in any country. |
English 2009 | eng_2009 | googlebooks-eng-all-20090715 | |
English Fiction 2012 | eng_fiction_2012 | googlebooks-eng-fiction-all-20120701 | Books predominantly in the English language that a library or publisher identified as fiction. |
English Fiction 2009 | eng_fiction_2009 | googlebooks-eng-fiction-all-20090715 | |
English One Million | eng_1m_2009 | googlebooks-eng-1M-20090715 | The "Google Million". All are in English with dates ranging from 1500 to 2008. No more than about 6000 books were chosen from any one year, which means that all of the scanned books from early years are present, and books from later years are randomly sampled. The random samplings reflect the subject distributions for the year (so there are more computer books in 2000 than 1980). |
French 2012 | fre_2012 | googlebooks-fre-all-20120701 | Books predominantly in the French language. |
French 2009 | fre_2009 | googlebooks-fre-all-20090715 | |
German 2012 | ger_2012 | googlebooks-ger-all-20120701 | Books predominantly in the German language. |
German 2009 | ger_2009 | googlebooks-ger-all-20090715 | |
Hebrew 2012 | heb_2012 | googlebooks-heb-all-20120701 | Books predominantly in the Hebrew language. |
Hebrew 2009 | heb_2009 | googlebooks-heb-all-20090715 | |
Spanish 2012 | spa_2012 | googlebooks-spa-all-20120701 | Books predominantly in the Spanish language. |
Spanish 2009 | spa_2009 | googlebooks-spa-all-20090715 | |
Russian 2012 | rus_2012 | googlebooks-rus-all-20120701 | Books predominantly in the Russian language. |
Russian 2009 | rus_2009 | googlebooks-rus-all-20090715 | |
Italian 2012 | ita_2012 | googlebooks-ita-all-20120701 | Books predominantly in the Italian language. |