Digital coupon distribution is ramping up quickly, according to an analysis by Minneapolis-based Marx, a Kantar Media division. On websites monitored by Marx, which include those of several large supermarket and drug store chains, digital coupon “events” increased by 30.5% through the first nine months of 2012, compared with year-ago coupon distribution. More than 681 manufacturers have distributed digital coupon offers on these websites this year from January through September, an increase of 15.2% vs. the same period in 2011. Food categories represented 50.9% of digital coupons, led by dry grocery, with 25.7% (up 1.6 points over a year ago). Marx also examined visits to the coupon areas of retailer websites, and found that even though Walmart.com boasted 58.2 million unique visits in September — vs. 36.8 million at Target.com — visits to its online coupon area were only about one-third of those to Target.