Wordtracker does not provide daily search counts or other daily metrics. They haven't done this in over 2 years.

All WT metrics are annually. If you click the question mark beside the searches column, it explains the following:

"'Searches' is the number of times that the keyword has been searched for in our partner search engines in the US.

The data currently contains 558,778,307 searches over 365 days."

The same applies to their free keyword tool.

Please keep in mind that all data from all keyword research tools is a representative sample, not actual search counts. This is clearly explained on WT's site, Keyword Discovery's site and many others. There simply is no way the keyword research tool could physically house all the searches from all the people even in just 1 country, much less globally. Even Google's free kwr tool offers representative samples. (Which is also stated on their site.)