How to open a tourism agency?

How does the tourism department measure ROI on the advertisement done by that department which happens to be a Government Agency?

• When a tourism department, which is government agency, advertises for state tourism, how is the ROI on the advertisement is measured. Currently I am listening to lot of Radio ads for Gujarat in Pune (Maharashtra) and probably are run in other states/cities as well. Not sure how would Gujarat Tourism Department be measuring the success of the campaign and hence this question. Since Tourism department wouldn't be receiving any money directly or probably won't even know if the tourist has come due to the ad, I am finding it difficult to understand.

• Answer:

  there is no accurate way to measure, we can gate estimate ROI on basis of following things, know how much tourist visa was issued, collection made by hotel by foreigners, entry ticket fee collected. use of visa by foreigners.  this much we can track & make estimation, rest things we cannot track like. cash purchase made by them. If cross country ready to provide information then we can get almost accurate amount spent by foreigner. eg. how much amount of $ they converted in Indian rupees & how much balance was return.