Populus conducted a demographically representative online survey of 2,059 adults in England and Wales, from 22-25 February 2018 (attached below). In previous years, the survey has been conducted using a telephone methodology (Computer Assisted Telephone Interview, or CATI, using a mix of mobiles and landlines). See p18 of the full http://bit.ly/2uqovMY Trust in Charities report for full details around quantifying the modal differences between the two methods.