add density field to cityboundaries.geojson

[emillipede]

AS A/AN:
user

WHEN I:
view the choropleth map (#301)

I WANT TO:
see color gradation by trees/square mile

the cityboundaries.geojson contains a field that documents each city's (and unincorporated la county) area and human population. Matt Stiles' data repository contains street tree counts for many LA county cities. for the cities Matt Stiles documented, I calculated public tree per square milage and per person values (see table below - CSV). I’d like to add a "density" field and a "tree count" field to the geojson with the trees/sq mile values. we don’t yet have public tree data about the other LA county cities (the ones not in this table).

for now, I think these static values are OK and simpler than processing/computing these values in the pipeline. the population data are a few years out of date, and the tree counts are at least one year out of date (in some cases, 10 years old). the density values are approximate.

Municipality	tree count	public trees/square mile	square mileage
Beverly Hills	29,000	5,078.8091	5.710
West Hollywood	9,000	4,761.9048	1.890
Santa Monica	35,099	4,173.4839	8.410
San Fernando	9,500	4,008.4388	2.370
Lawndale	7,400	3,756.3452	1.970
Cerritos	31,300	3,532.7314	8.860
South Pasadena	11,400	3,333.3333	3.420
Culver City	16,900	3,287.9377	5.140
Pasadena	71,000	3,072.2631	23.110
South Gate	20,900	2,886.7403	7.240
Bell Gardens	7,000	2,845.5285	2.460
Long Beach	140,000	2,761.3412	50.700
Alhambra	20,100	2,634.3381	7.630
San Marino	9500	2,519.8939	3.770
Inglewood	21,800	2,398.2398	9.090
San Gabriel	9,900	2,391.3043	4.140
Temple City	9,000	2,250.0000	4.000
Norwalk	21,400	2,203.9135	9.710
Pomona	50,000	2,175.8050	22.980
La Mirada	17,000	2,173.9130	7.820
Burbank	37,000	2,136.2587	17.320
Redondo Beach	13,000	2,093.3977	6.210
Covina	14,600	2,076.8137	7.030
West Covina	33,000	2,050.9633	16.090
Whittier	27,800	1,897.6109	14.650
Glendale	56,000	1,838.4767	30.460
Paramount	7,800	1,649.0486	4.730
Santa Clarita	112,000	1,581.4742	70.820
Lomita	3,000	1,570.6806	1.910
Artesia	2,500	1,543.2099	1.620
Downey	18,500	1,490.7333	12.410
Arcadia	15,600	1,427.2644	10.930
Bellflower	8,400	1,361.4263	6.170
Diamond Bar	20,100	1,351.7149	14.870
Carson	22,500	1,201.2814	18.730
Duarte	7,900	1,177.3472	6.710
El Segundo	6,400	1,172.1612	5.460
LA City	545,000	1,162.1212	468.970
El Monte	11,000	1,150.6276	9.560
Rancho Palos Verdes	13,500	1,002.2272	13.470
Santa Fe Springs	8,700	976.4310	8.910
San Dimas	10,400	691.4894	15.040
Agoura Hills	5,100	653.8462	7.800
Glendora	12,600	645.8227	19.510
Lancaster	46,000	487.9084	94.280
Malibu	7,400	372.6083	19.860
Walnut	3,200	355.9511	8.990
Palmdale	19,000	178.7394	106.300
LA County	99,000	37.3162	2653.000
Ventura County / Simi Valley	16,400	7.4275	2208.000

note about Santa Monica* - the number recorded here is larger than Matt Stiles' recorded tree count for SM