The regional council said last October and November, its Metro bus service missed 8.2 per cent of scheduled trips.
This included all urban and school routes for Greater Christchurch, as Timaru had not had a driver shortage, it said.
Last month that number dropped to 5.4 per cent, or 2737 trips. On average, it worked out to about 88 missed trips per day in March.
An RNZ investigation has found hundreds of bus services were also being cancelled every day in Auckland and Wellington.
A council spokesperson said its operators had been recruiting heavily for bus drivers.
"We have had approximately 50 new staff start since late February… our operators are now short by about 10 drivers," they said.
"However, many of the drivers recruited recently are still in training and not yet active on the network."
They said the downward trend in missed buses was expected to continue as they began driving.
For example, on March 3 there were 175 missed trips, compared to just eight on April 3.
Despite the missed trips, passenger numbers were increasing - last month reaching 95 per cent of pre-Covid-19 numbers, the spokesperson said.
"In February and March, we celebrated more than one million monthly passengers.
"With this increasing patronage and the recent driver wage increase, we look forward to more drivers joining the Metro network, and our services recovering further as a result."
