Every week I get calls from Forrester clients asking how they can measure engagement on Facebook and Twitter. And every time, I tell these marketers the same thing: You must stop measuring social engagement.

I understand that it’s hard to measure social success: Marketers tell us measurement is their single biggest social challenge. And I know that tracking engagement feels like an easy option. But the simple fact is, engagement is not a useful social marketing success metric.

We’ve spoken with scores of social vendors who measure engagement, and none has proven if — or how strongly — engagement correlates to business success metrics like loyalty or sales. Even Facebook itself says engagement doesn’t prove success: In its marketing collateral, Facebook warns that engagement metrics are “not a reliable indicator” of whether social marketing improved your business.

Some say that engagement matters because when people like or share your posts, they reach a broader audience. And your social posts’ reach will go up slightly if people engage. But engagement can’t overcome declining organic reach. Brands’ Facebook reach is already low, and heading lower still. And data from Socialbakers shows that even the Facebook posts that receive the highest level of engagement still get 99% of their reach from paid, not organic, impressions.

So why do social marketers still focus on engagement data? Because it’s easy to collect. But it’s simply the wrong data. That’s why CMOs and other senior marketers rarely ask us about engagement — instead, it’s mostly social marketing strategists and digital marketing directors who want to track these metrics.

If you’re a social marketer and you want to impress your boss — and get more funding for your efforts — then it’s time to stop measuring social engagement. Instead, bring your CMO reports from sales tracking vendors, platforms that collect data into customer databases, and survey tools. You’ll be speaking their language, and your budget will benefit.

For much more detail on how to effectively measure the performance of social marketing programs, including specific tactics you can use and the names of vendors who can help, check out our new report “Stop Measuring Social Engagement.”