The magnitude of digital divides can also be expressed in terms of time lags, i.e. in terms of the time delay for particular sub-groups to achieve the same level of Internet usage as the population on average.
Such time distances (s-distances) were calculated between the April 2002 levels of Internet usage for the selected socio-economic and demographic groups and the (earlier) time when corresponding levels had been achieved by the population overall. The smallest time lag was that for gender, followed by age (50+), income (lowest quartile) and low education (early school-leavers) . The gender time lag for Internet usage overall is only about 5 months, meaning that the population overall reached the April 2002 levels of usage by women five months earlier, whilst for the low education group it was more than 4 years. Time distances can also be used to compare penetration rates for different indicators and different categories. For example, the time lag for “total Internet usage at home” behind “total Internet usage” was generally about 8 months although for some groups it was slightly longer.