Billions

In Math today we worked on place value through the billions.  We talked about when we've heard numbers in the billions.  Ruth brought up "population."  We made predictions about which populations were in the billions.  A small team looked for data.
Here's what they found:

TOP TEN COUNTRIES WITH THE HIGHEST POPULATION
#	Country	2000 Population	2010 Population	2012 Population	2050 Expected Pop.
1	China	1,268,853,362	1,330,141,295	1,336,718,015	1,303,723,332
2	India	1,004,124,224	1,173,108,018	1,189,172,906	1,656,553,632
3	United States	282,338,631	310,232,863	313,232,044	439,010,253
4	Indonesia	213,829,469	242,968,342	245,613,043	313,020,847
5	Brazil	176,319,621	201,103,330	203,429,773	260,692,493
6	Pakistan	146,404,914	184,404,791	187,342,721	276,428,758
7	Bangladesh	130,406,594	156,118,464	158,570,535	233,587,279
8	Nigeria	123,178,818	152,217,341	155,215,573	264,262,405
9	Russia	146,709,971	139,390,205	138,739,892	109,187,353
10	Japan	126,729,223	126,804,433	126,475,664	93,673,826
TOP TEN Countries		3,618,894,827	4,016,489,082	4,054,510,166	4,950,140,178
Rest of the World		2,466,012,769	2,829,120,878	2,875,544,988	4,306,202,522
TOTAL World Population		6,084,907,596	6,845,609,960	6,930,055,154	9,256,342,700

Then a student wondered how it's possible for India's population to surpass China's.  After a lot of guesses, we got to, "Babies!"  Understanding the meaning behind digits and numbers is fascinating.  Understanding some of the factors that make up population is overwhelming (i.e. religious views or socioeconomic realities that would lead to having more than one baby).