Last we heard (Mr Sharif may have told TOI), BMTC said that public transport accounts for 48% of trips in the city. Another stat from Ministry of Urban Development had put public transport's share in Bangalore to about 35%. So, there we have, a range of 35% to 48%, and we know that in Bangalore, public transport virtually equals BMTC.
Whats the real, and meaningful percentage that BMTC carries anyway. How about some way of cross checking and verifying these stats? Meaningful means carrying morning and evening commuters, because thats where we need help right now.
Commuter stats
Lets go with MoUD's 35%, and assume that they are talking commuters. Add company, school, college owned buses (these may not be considered public transport) etc to this stat. 35 + 5 = 40%. And then, don't assume that the rest = 60% doesn't use private vehicles to commute - take out folks who walk, use bicycles, or pool in someway. Give out 5%. Now, we get 55% - Bangalore commuters use private transport.
Now, Bangalore's population = 70 lakhs. Lets say those who commute (includes workers, students/moms 'commuting' to school/college) form 30% of this number. 21 lakhs.
55% of this 42 lakh ~ 12 lakhs. This could be the number that uses private transport of some form.
Now, vehicle data
How about a quick cross check with the vehicle data in our city. Quoting a Deccan Herald article via BangaloreBuzz:
“The total number of two-wheelers contribute to 75 percent of the total vehicles while 16 per cent are cars. Autorickshaws make up 4 per cent, trucks 3 per cent and buses and other motor vehicles constitute about a per cent each of the total,” he told Deccan Herald.
We are told there are 26 lakh vehicles (various data points say 26-28 lakhs rt now) in our city. Using above split, we could be talking 20 lakhs two wheelers, 4.2 lakh cars.
Assuming 70% of these vehicles gets used everyday for commutes, 14 lakh commute via 2-wheelers, and 3 lakh via cars.
The total? 14 + 3 = 17 lakhs.
Of course, the numbers don't match, but it depends on two key assumptions above:
- Percentage of population that commutes (aka working population of Bangalore). assumed here = 30%
- Percentage of private vehicles that get used for commutes. Assumed here = 70%
Adjust the two, and we get some numbers to play with.
Another angle - BMTC's carrying capacity?
Wait, wait. There is posibly another angle for generating numbers, but we would again need some big assumptions there.
BMTC has about 4000 buses, assume that all are in use during commute hours. Assume each bus can seat 40. 40*4000 = 1.6 lakhs is BMTC's carrying capacity. But this is a meaningless stat by itself as one bus picks and drops multiple people on its route.
BMTC may be carrying 35% of commuters (as per MoUd stat), but whats that absolute number? BMTC claims to carry 35-37 lakh passengers per day, but this data most likely includes people making multiple trips (they go by ticket sales?). Commuters would use BMTC twice a day. That simple rule lowers this number to 18 lakhs. Put a factor for multiple tickets (change of route leading to more tickets), say reduce the number by 20%, you get abt 14 lakhs.
So, to carry 14 lakh people during morning commute, BMTC is using 4000 buses. We are talking 350 people 'carried' per bus during commute time. Fair enough number here, each bus, though can seat 40 at a time, would be 'touching' 8-9 times that number via multiple people using it.
Conclusion
Its a jungle with huge cobwebs if you venture into stats. Wish we could see backing data for BMTC and MoUD's stats. We need those to make sure that people who collected the statistics did a dillgent enough job. You never know. And with so many assumptions to make, we can never cross-check those stats ourselves. I tried, and I think it didn't lead to much.
Will try to make this better by replacing some assumptions with real data provided by MoUD etc.
ಪ್ರತಿಕ್ರಿಯೆಗಳು
why this?
Why this meandering post, some asked. I was inspired by our PM's recent admission that stats gathering mechanism in our country may be in the need of urgent overhaul. We take all numbers thrown at us for granted. Will be good for us to probe them a bit, how was the stat collected? what assumptions were used when doing extrapolations?
Good stats are essential, and most important inputfor any planning or designing.
Forgot about the wilbur smith study