The behaviour of taxi drivers was the largest reason for complaints about the sector last year.
Of a total 998 complaints received in 2016 almost half, or 444, had to do with taxi driver behaviour.
The figures are published in the latest National Transport Authority (NTA) Taxi Statistics for Ireland.
The next largest category of complaints after conduct, at 348, was overcharging and matters relating to fares while there were 172 complaints around hiring and booking difficulties and 32 about the condition and cleanliness of taxis.
In 2014 the NTA introduced a nationwide complaints process for taxis, hackneys, limousines and dispatch operator services nationwide.
At the end of December 2016 there were 20,804 active taxi licences in Ireland. This includes taxis, hackney cars, wheelchair accessible taxis, wheelchair accessible hackney cars, local area hackney cars, and limousines. The figure is down 24 per cent from a high of 27,429 in 2008.
Last year there were 15,961 regular taxis in Ireland, 1,838 regular hackney cars, and 1,741 limousines. On top of which there were 1,185 wheelchair accessible taxis and 69 wheelchair accessible hackney cars.
According to the report 80 per cent of taxis in Ireland are more than five years old while 88 per cent of taxi drivers are over 40 years of age.
Some 3,266 regular taxis are over 10 years old, with just 1,585 under three years old.
The report shows the extent of the decline in the number of active taxi drivers. Last year there were26,420 taxi driver licences in Ireland, of which 54 per cent in Dublin. This is a 44 per cent decline from the peak of 47,529 taxi driver licences recorded in 2009.
By age group, 32 per cent of taxi drivers are between 50 and 59 years of age, with 27 per cent in the 40 to 49-years of age group. According to the report 23 per cent of drivers are aged between 60 and 69 with just 11 per cent aged between 30 to 39.
Only 1 per cent of taxi drivers are aged between 20 and 29.
The NTA said its compliance officers carried out 90,000 checks on drivers and their vehicles in 2016, a three-fold increase on 2015.
In 12,012 cases more detailed face-to-face audits took place, which led to 1,099 fixed penalty notices being issued.
The number of wheelchair accessible vehicles has increased in recent years, to 1,254, from 916 in 2013, due to grants enabling operators buy such vehicles.
