From the new WON:
"Extreme Rules this year was listed by WWE as doing 131,000 domestic buys and 104,000 overseas buys, for 235,000 total. The domestic number is down 17.6% and the overseas number is down 7.1% from last year’s 159,000 and 112,000 numbers, totaling 271,000. […] As far as profit margin goes, a Lesnar show needs to do about 70,000 added buys to where the profit would be the same. So this was down from last year, but last year was a Lesnar show. The 2011 Extreme Rules show did 216,000 total buys and 108,000 domestic. So, more than any show to date, Lesnar didn’t increase business anywhere close to enough to justify the expense."
The golden goose appears to be running out of eggs, but really they've made him into just another guy so it's hard to be too surprised about that. Having him headline a B show, in a match that no one wanted to see, was also a huge mistake.