Disruptive Advertising analysed tens of millions of dollars’ worth of Google Adwords ad expenditure (about one hundred billion impressions) over the course of three years.
These are the gems they unearthed:
1. Search keywords that did not result in a conversion accounted for 61% of all budgets.
2) If you’re wasting money on the wrong search terms, changing your ad copy or landing pages has a 1.2% probability (virtually no chance) of increasing your CPC.
Your cost-per-conversion (CPC) will rise by between 44 and 72% for every 10% in lost ad expenditure. You can save between 264% and 432% on CPC if you avoid bidding too much on the wrong search phrases (61%).
Source: www.searchenginejournal.com