How can I find out how frequently a keyword or phrase is used on Twitter?

Factual Questions
1

Are there any free Twitter Analytics sites?

The site

analyzes up to 100 tweets at a time. This is a very small amount – I can see a trend only for one hour.

For example, is there a way to find how often a phrase like “twitter analytics” have appeared in tweets over the years.

2

There are many Twitter Analytics sites.

Almost all of them require filling in tons of forms. Some are very expensive.