This website created by Mark Davies is very useful to find words of American English from 1923 to the present, just by choosing the date and the word to look up. This corpus has more than 100 million words, as found in TIME magazine.

Some of the advantages of it, is that we can see how words and phrases have increased and decreased in usage, and how they have changed their meaning over time, by looking at changes in collocates (co-occurring words). We can also have the corpus generate a list of words that were used more in one period than another, even when you don’t know what the specified words might be.

To look up a word, we can choose the type of display:

• CHART: This option presents “bar charts” that indicate the overall frequency for all matching words or phrases in each section of the corpus. This is probably the best option for comparing between different genres, or to compare time blocks.
• LIST: With this option, we see a listing of each individual word or string that matches the query. 
• COMPARE WORDS: This allows us to compare the collocates (nearby words) for two different words. When selected, we will see the frequency of each matching string for the following nine groupings: [genres] spoken, fiction, magazines, newspapers, academic; [time blocks] 1990-1994, 1995-1999, 2000-2004, 2005-2007. When it is not selected, you will see the overall frequency in the entire corpus. 

In the search string:

• You enter the basic search string (words). We can also enter “context” words and indicate how many words away this is with. We can use parts of speech as part of our query. For example, [j*] eyes in [1] would find a two word string, composed of a form of eyes immediately preceded by an adjective.
• We can also create “User lists” or “customized lists”, relating to a certain topic, words that are grammatically related, or any other listing.

In the section:

• We can chose the date, or dates to compare and the minimun frequency.

Now that we have seen all the option of search and we have given a little introduction of how to use them, we can try and see all the possibilities this program offers us, wich is very useful for doing any research or statistics.