With a Few Assumptions
I am drinking soy milk at a breakfast shop near the station.
It is still early, before full wakefulness arrives.
In front of me, people on YouBike pass one after another.
Some wear suits.
Others carry backpacks.
Each time the light changes, a few more flow through.
It feels slightly excessive.
How many YouBike bicycles are there in Taiwan?
I do not know the exact figure.
But by stacking a few facts and assumptions, a rough scale begins to appear.
So I start calculating, quietly, in my head.
Working backward from usage
I begin with the most visible number.
I recall a news report stating that
YouBike in Taipei is used about 200,000 times per day.
This is not a count of bicycles,
but a count of rides.
How many times does one bicycle get used in a day?
In the early days of YouBike,
a figure of twelve rides per bicycle per day was often mentioned.
Conditions have changed since then.
The system is now mature,
with clear peaks and quiet hours.
Here, I assume a more conservative figure:
ten rides per bicycle per day.
200,000 rides ÷ 10
= 20,000 bicycles
This suggests the scale of YouBike within Taipei City.
Next, I extend this number to Taiwan as a whole.
Taipei’s daytime population is about 3.5 million.
Taiwan’s total population is roughly 23 million.
Adjusting simply by population ratio:
20,000 × (23 million ÷ 3.5 million)
≈ 130,000 bicycles
It is a large number,
but not implausible when thought of as urban infrastructure.
Building up from station density
Next, I approach the question from placement.
In built-up areas,
YouBike stations are said to be spaced roughly every 300 meters.
On a grid of 300 meters,
one station covers about 0.09 square kilometers.
Taipei City covers about 275 square kilometers.
Excluding mountains and less-used areas,
I assume half functions as actual urban space.
275 × 0.5 ≈ 138 square kilometers
138 ÷ 0.09 ≈ 1,500 stations
The number of bicycles per station varies by location.
Here, I assume an average of twenty.
1,500 × 20 = 30,000 bicycles
This does not sharply contradict
the earlier estimate of about 20,000 bicycles in Taipei.
Considering variation—
thirty or more in busy districts,
around ten in residential areas—
the range feels reasonable.
I then extend this figure to the whole of Taiwan.
30,000 × (23 million ÷ 3.5 million)
≈ 200,000 bicycles
This estimate runs somewhat higher than the previous one.
Considering the user base
Finally, I think about who actually uses YouBike.
Taiwan’s population is about 23 million.
The main users are likely
high school and university students,
along with a portion of working adults.
Here, I assume that five percent of the population
are regular users.
23 million × 5%
= 1.15 million people
Not everyone rides every day.
Some ride once.
Others ride twice, commuting back and forth.
I assume that half of these users
ride twice per day.
1.15 million × 0.5 × 2
= 1.15 million rides per day
If each bicycle supports ten rides per day:
1.15 million ÷ 10
= 115,000 bicycles
The numbers begin to converge.
When estimates converge
These three estimates come from different starting points.
From usage: about 130,000 bicycles
From station density: roughly 150,000 to 200,000
From user base: about 120,000
There is no extreme divergence.
Allowing for error,
the total number of YouBike bicycles in Taiwan
likely falls somewhere between 120,000 and 180,000.
At least,
“tens of thousands” seems too small,
and “several hundred thousand” too many.
As the soy milk cools
By the time I finish my soy milk,
the morning rush has eased.
The YouBike that were streaming past earlier
now return quietly to their stations.
No one is thinking about how many there are.
They do not feel excessive,
nor insufficient.
Yet to maintain that sense of balance,
well over one hundred thousand bicycles
circulate through the city each day, in silence.
There are that many,
and still they do not feel like too many.
That, perhaps,
is part of this city’s design.
Addendum
Later, I look it up.
The reported total number of YouBike bicycles
is about 93,000.
This is somewhat lower
than the 120,000 to 180,000 I first imagined.
The reason seems simple.
My estimates assumed that usage everywhere in Taiwan
resembled usage in central Taipei.
In reality, conditions differ.
In regional cities,
the number of users is smaller.
Station density is lower.
Turnover rates are not as high as in Taipei.
I had stretched the sensation of the city center
across the entire island.
The scene of bicycles disappearing one after another
during the morning rush
belongs only to the places where circulation is most intense.
Seen nationwide,
many YouBike bicycles move at a quieter pace,
placed farther apart.
Even so,
the fact that more than 90,000 are maintained
leaves a stronger impression.
This system does not rely
only on dense success in a few areas.
It holds together even where bicycles sit unused,
and time passes more slowly.
What I saw at the breakfast shop
was simply the fastest-moving section
of a much larger whole.
