Bus Routes, an Ageing City and a Misleading Percentage
The city of Naka (population 42,000) is reviewing its bus network before the February budget.
| Population by age | 2000 | 2020 |
|---|---|---|
| 0–14 | 5,880 | 4,200 |
| 15–64 | 27,300 | 23,100 |
| 65+ | 8,820 | 14,700 |
Bus use fell from 1.9 million rides in 2000 to 0.9 million in 2020. Fares bring in ¥210 million a year; operating the network costs ¥510 million, so the city pays ¥300 million. The transport department proposes closing 3 of the 8 routes to save an estimated ¥120 million a year. The three routes together carry 1,100 riders a day, of whom 62% are 65 or older. One route serves the prefectural hospital; one serves two of the city's four high schools; one runs through a district with no supermarket within 2 km. Service frequency on all routes was cut by about a third in 2008. The mayor wants a written review that separates what the numbers prove from what they only suggest.
1. Calculate the ageing rate in 2000 and 2020, and say what the change implies for how a bus route should be judged.
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Ageing rate (65+ ÷ total):
- 2000: 8,820 ÷ 42,000 = 21.0%
- 2020: 14,700 ÷ 42,000 = 35.0%
Supporting changes: 0–14 fell 5,880 → 4,200 (−28.6%); 15–64 fell 27,300 → 23,100 (−15.4%). The working-age group that supplies most car drivers shrank fastest in absolute terms (−4,200 people), while the group least able to drive grew by 5,880.
Implication. A route's value cannot be read from its farebox. In 2020 the system recovered 210 ÷ 510 ≈ 41% of cost, and each ride cost 510,000,000 ÷ 900,000 = ¥567 to provide against ¥233 in fares. Judging routes only by revenue per ride would scrap exactly the routes whose users have no alternative - the same logic by which a fire station would fail a profit test.
Caution to flag: the total is 42,000 in both years, in a city that reports shrinking cohorts. The review should confirm the totals are on the same boundary (no merger, no rounding) before the percentages are quoted.
2. The department argues: 'Ridership fell by more than half, so these routes are no longer needed.' Identify the flaw and give the strongest counter-argument the data allows.
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The flaw: cause and effect are mixed. Rides fell 1.9M → 0.9M, a 52.6% drop. But frequency was cut by a third in 2008. Cutting service removes trips and drives riders away, so part of the fall is the department's own earlier decision, not evidence of no need. The fall also tracks a shrinking younger population: with 0–14 down 28.6% and 15–64 down 15.4%, some decline was unavoidable.
The counter-argument from the data:
- The three routes carry 1,100 riders a day ≈ 401,500 rides a year. Saving ¥120 million on that is about ¥299 per ride saved - a real figure, but it must be compared with the cost of the substitute.
- 682 of those riders are 65+ (62% of 1,100). If each needed a taxi voucher of ¥500 a trip instead, the city would spend more than it saves.
- The three routes are not interchangeable: hospital access, school access and food shopping are three different needs, and only the school route has a predictable timetable (school hours only).
Conclusion: the department has shown that demand is lower, not that need is lower. Demand responds to supply; need does not.
3. Design a compromise for the mayor, and name the one number you would check before adopting it.
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Compromise ('trim the when, not the where'):
- Hospital route: keep all day, but reduce to a clock-face hourly service off-peak.
- School route: run it at school start and finish only, and contract the two high schools to share a school bus; this alone may take one vehicle off the road.
- Third route: replace with a demand-responsive taxi (デマンドタクシー) in the off-peak, keeping a fixed morning and evening run for commuters. Estimated saving: roughly ¥50–60 million instead of ¥120 million, with none of the three needs cut off.
The number to check before adopting it: how many residents aged 65 or over live more than 500 m from a remaining stop and have no car in the household. That single figure converts the plan from a route map into a statement about people. A second check: how many of the 1,100 daily riders have no alternative mode (no car, no family driver) - if most do, the saving is mostly a transfer of cost to households, not a saving at all.
The mayor's request matters here: the numbers prove the subsidy is ¥300 million and the ageing rate is 35%. They only suggest that the three routes are the ones to cut.