3FM submitted a Freedom of Information request to the department asking for the figures for the past five years.

In recent months the department's found itself embroiled in rows with a number of Island organisations over charges for using the TT initials.



The DED's responded to 3FM's request by providing figures for each of the past six financial years.

Licensing the TT trademark raised just under £250,000 between April 2011 and March 2012 - a figure that more than doubled the following year.

The amount grew steadily until 2015/16, when it leapt to £813,000 and then last year reached a peak of more than £878,000.

In the House of Keys next week, Ayre and Michael MHK Tim Baker will ask questions about the department's licensing policy.