Niagara data projectMost parks, or most land? Two kinds of percentage from the City of Niagara Falls parks file
We looked for parks data across the St. Catharines - Niagara census metropolitan area. The City of St. Catharines publishes a parks layer, but its record carries no licence, so we did not use it. The City of Niagara Falls, a municipality in the same metropolitan area, publishes its parks under an open government licence. So the numbers here describe Niagara Falls only, and we worked them out ourselves from the copy we downloaded on 22 October 2026.
City of Niagara Falls Community Parks and Trail Lands: our calculation of each park type’s share of the 109 parks and of the 441.61 hectares in the file| Type | Parks | Share of parks | Hectares | Share of land |
|---|
| NEIGHBOURHOOD | 61 | 56.0% | 91.29 | 20.7% |
| CITY WIDE | 26 | 23.9% | 220.68 | 50.0% |
| COMMUNITY | 22 | 20.2% | 129.64 | 29.4% |
Neighbourhood parks are more than half of all the parks but only about a fifth of the land. City-wide parks are under a quarter of the parks yet half the land. Both statements are true at once, and which one you quote depends on the question you were asked. Both shares come out of one short Python program, which twelve-year-olds in our classes write themselves:import csv
parks = {}
land = {}
with open("niagara-falls-parks.csv", encoding="utf-8-sig") as f:
for row in csv.DictReader(f):
kind = row["Type"]
parks[kind] = parks.get(kind, 0) + 1
land[kind] = land.get(kind, 0) + float(row["Area_HA"])
total_parks = sum(parks.values())
total_land = sum(land.values())
for kind in parks:
print(kind, round(100 * parks[kind] / total_parks, 1), "% of parks,",
round(100 * land[kind] / total_land, 1), "% of land")
Two dictionaries, one loop
parks counts each type; land adds up each type’s hectares. Both fill in the same pass through the file, and the totals come from adding each dictionary’s values.
Share means divide
A share is part divided by whole, times 100. The same type gets two different shares because the whole is different: 109 parks in one case, 441.61 hectares in the other.
A decision to inform
This is the Grade 8 idea in small. If a town wanted more parks within walking distance, which share matters? If it wanted room for sports fields? Children argue it out, using the numbers.
Why the shares add up to 100.1
Add the rounded park shares: 56.0 + 23.9 + 20.2 = 100.1. The land shares, 20.7 + 50.0 + 29.4, also make 100.1. Nothing is wrong. Each share was rounded to one decimal place on its own, and the small rounding gains happened to pile up. Unrounded, they make exactly 100. Children who meet this once stop being alarmed when a newspaper chart adds to 99 or 101.
The City scores its own file, too. The dataset description shows an “Open Data Quality Rating (Beta): 89.1/100” as of 19 October 2026, with separate scores for Completeness (82.4), Validity (88.2), Recency (92.3), Uniqueness (100.0) and Understandability (90.8). A class can discuss what each word means for a data user; we do not average the scores ourselves. In our download, 90 records are dedicated parks, 15 dedicated trails, 3 non-developed and 1 a dog park, and 35 parks are under one hectare. We print no park names, since several honour people. Contains information licensed under the Open Government Licence - Niagara Falls (terms of use). The City does not endorse this page.
