RE:RE:US Shale By 2016, Marathon came back and drilled more wells armed with new knowledge and drilling techniques. It drilled longer laterals and used much more frac fluid. Only four of the completions outperformed the older ones, and on average, the IP peaked at 32,500 boe per month (less than the older average) and declined to just 8,000 boe per month in seven months as opposed to the 13 months the first time around.
In other words, Marathon drilled more aggressively in 2016 and arguably came up with less impressive results.
This is not necessarily indicative of the entire shale industry by any means, but it does highlight some of the problems with relying too much on the initial production metric. Yes, IPs have climbed over time, but some of these wells are petering out faster than older wells.
In a way, this trend is understandable since it took place in an area that had already been drilled. But as U.S. shale basins mature, the industry will need to increasingly rely on similarly well-developed areas.