Glide path or crash landing? Pennsylvania Manufacturing.
One of those things that needs a little historical perspective to even begin thinking about. Here is Pennsylvania's manufacturing employment since 1969. Not exactly much change in trend which is remarkable in itself. Through significant booms and busts, not much deviation from trend.
For Pittsburgh it is not such a smooth glidepath. First there was the crash landing, and later in the 1990's I suspect the trend would look more like the state's if you took out the growth and decline of employment at the former Sony Plant in Westmoreland County which expanded a lot in late 1990's only to go away completely.