Or is this really a throwback chart?
Measurement elements on this chart have been essentially the same since the mid 90’s. Sure, email marketers have honed the craft a bit, gotten smarter in their focus and test strategies. But the same old triggers exist for excellent email: solid subject lines, relevant content, personalization. It remains crucial to A/B test subject lines on a regular schedule.
Good to know that if you maintain the focus this chart implies, and have a consumer relevant product or service, your results will increase.