Douglas County, Nebraska
Demographics
Table:
Historical population

Census	Pop.	Note	%±

1860	4,328	—
1870	19,982	361.7%
1880	37,645	88.4%
1890	158,008	319.7%
1900	140,590	−11.0%
1910	168,546	19.9%
1920	204,524	21.3%
1930	232,982	13.9%
1940	247,562	6.3%
1950	281,020	13.5%
1960	343,490	22.2%
1970	389,455	13.4%
1980	397,038	1.9%
1990	416,444	4.9%
2000	463,585	11.3%
2010	517,110	11.5%
2017 (est.)	561,620	[10]	8.6%
US Decennial Census[11]
1790-1960[12] 1900-1990[13]
1990-2000[14] 2010-2013[1]

From the following table concerning 'Douglas County, Nebraska' — "Demographics" section, create one factual sentence about the highlighted cells, without adding extra data and return it as JSON: {"answer": "YOUR ANSWER"}.