This is what you call level? Because if you passed fifth grade math, you'd be able to recognize that as a downward slope.
Sure, the slope in the Reagan years is better than it is the Ford and Carter years, but you can clearly see that in the Ford/Carter years, the only drops in real wages were during the 1973 oil crisis and the 1979 oil crisis. I'm not saying that Ford and Carter aren't to blame for the oil shocks (they are to a large extent), but this is a failure of their foreign policies, not their economic policies.
Now look at the Reagan years. What oil crisis did he have to cause a drop in real wages? None? So what does that say about Reaganomics?
And even if you do think Reagan did better than Ford and Carter. So what? The economy under Carter might have been better than Zimbabwe's economy is right now, but that doesn't mean Carter did a good job. A good job on Reagan's part would have been reversing the drop in real wages (like what happened in 74 - 78, according to the graph), not prolonging it for another eight years.