With respect to "Growth of Growth", wouldn't the chart ALWAYS look like that, with the near end trailing downwards? The sampling time is decreasing logarithmically, so unless you are sitting right on top of the singularity/production revolution, it should always look like that.

Just got thinking about what happened around 1950 specifically and couldn't find any real reason for it to drop off right there. WWII was well over, and the gold exchange standard remained for another 21 years, and those are the two primary framing events for that timeframe, so far as I can tell.