Economics has about 230 places and about 1300 applicants - this can be seen in the online prospectus. You can see the percentage of applicants receiving offers here.
I'm not quite sure what you're reasoning behind asking is, but if you are working out how likely it is that you will get an offer, then as long as you reach the entry requirements, have a good personal statement etc, then you have every chance to get an offer. Try not to look too much into the stats as they'll change every year.