Cycle use has fallen in many parts of Britain, with the falls greatest in the south and east of England.
CTC believes this change is due mainly to a lack of commitment from both local authorities and national government to cycling.
The data, published by the Department for Transport , comes from the Active People Survey, a large survey of people's physical activity habits compiled by Sport England.
It is terrible that cycle use appears to be falling in many parts of England – which is probably a direct result of the failure to provide space for cycling. Thousands of people have already written to their councillors calling for space for cycling  on main roads and reduced speeds and through traffic on residential streets.
CTC Senior Campaigner
Questions about people's general cycling were included after CTC suggested to the Department for Transport would be useful to monitor changes in cycle use.
CTC believes that reluctance from local authorities to provide space for cycling , coupled with a failure by police to enforce traffic law  and by national government to fund cycling properly have all conspired to allow cycling levels to drop.
Where is worst?
The biggest declines have been observed in the South East, South West and the East of England, while London and the West Midlands have remained at the same level as the year before.
Data should be used with caution as sample sizes are small and seasonal effects could mask overall changes in cycle use. Data are not available for anywhere outside England.
Change in cycle use between 2011/2012 and 2012/2013
Whereas 193 local authorities have declined or remained static, only 133 have shown increases. Oxford and parts of Kent have seen increases since 2011/2012, whereas falls have been observed in Essex and Middlesbrough.
Cycle use in 2012/2013 by % of people cycling once a month or more
The next map shows the proportion of people who cycle once a month or more in 2012/2013.
Click on each location to see the last three years of data and the local authorities position amongst all English local authorities.
This map shows that cycle use is still concentrated in the flatter, drier East of England, with the highest proportion (over 50%) in Cambridge, with high use also found in Oxford (42%) and York (27%).
By contrast, less than one in ten cycle once a month or more in the urban towns and cities in the north, such as Oldham, Burnley, Wakefield or Barnsley.
However, cycle use is pitifully small compared to our continental neighbours - 80% of people in the Netherlands cycle once a week or more.