We just updated the payment gateway index with December data from Spreedly and Shopify. 

That's our 4th month of data and there are some interesting trends evolving. We created the payment gateway index because failed transactions vary so dramatically on a gateway by gateway basis. Yet no data was out there to help merchants with their decisions. 

We explain our thinking in more depth here if you're interested. The data we share is solely from Spreedly and Shopify. It's a decent size pool to draw from but it is a limited pool. You should keep that in mind when reviewing the data. For example Shopify in particular does a lot of one time transactions vs recurring or subscription transactions. 

Recurring transactions tend to have a much higher success rate (based on the fact that the original one went through successfully and there were no issues) The more global a payment gateway the greater the chance that they're doing cross border transactions.Cross border transactions tend to have a higher failure rate (fraud filters) than in country transactions. We enjoy your feedback so keep it coming and we hope you find the data useful.