No, that’s illegal immigration and outsourcing to foreign countries to pay less taxes which is mostly a result of communist efforts. My father literally saw his power plant(s) and company (Exelon) cut benefits, perks, and scale # of workers too because of labor unions pushing hard and getting fucked over for it. They had so many easy perks and company parties at a local and state level. Things became much more centralized and management went for cheaper employees. Yes the free market is to blame, but not strictly capitalism. Both sides caused this. Union marxists who had it better than they complained and greedy capitalists who send nice try, now you lose.

The shrinking American middle class is not a problem ... 

In fact, many of those American middle class are getting promoted to a higher income bracket ... 

The middle class isn't shrinking because of the so called myth that the "rich are getting richer and the poor are getting poorer" but it's because much of the former middle class is too rich to be defined as middle class. Straight capitalism may have created more inequality but it's a system that created the most and 2nd most competitive economy in the world. Socialism is dysfunctional because it lacks the means of evolution and we don't have to look much further than an example such as Europe's labour policies where it's visibly losing ground in productivity compared to East Asia ... 

This. The gap between the rich and middle class is bigger, but the middle class is improving as well. Things are also becoming cheaper for us overall when it isn't heavily regulated by the government. That's why education and health care is going through the roof right now in costs.

Households spending more than $110 per person, per day are wealthy on this scale. 

I won't dispute that they do, but keep in mind that this is a topic about the world, not just two countries. India and Bangladesh combined only make up roughly 1.5 billion of the 7.3 billion that is the world's population. Even if the entirety of those countries fell into the poor group, it would be very possible for half of the Earth's population to be middle class or richer.

It is so funny that some people here are trying to base their experiences based on the outlier (USA). XD

Ignorance is a huge problem.

Brookings is a conservative thinktank under the guise of liberalism. Basically a Sargon but an organization.

Discredited, next.

Does this mean the wörld has become a better place?

You can't say that someone is rich just because they live in a richer country or city.  You still have to live and survive there.  Expenses vary by region and the same amount of money wont get you as far in those places.  Every region must be looked at separately.  This graph gives no insight into any of that.  

100% wrong. I earn roughly in that territory and spend virtually all of it every month, leaving me with hardly any savings. (in Manhatten) This is shared just between 2 people. 100k a month you can say is somewhat rich, 12k is not. There's a million things you can't do at 12k a month spending. Just because many make less than that doesnt make that rich. It only allows you to live relatively comfortably without worrying about being hand to mouth. That's not rich.