Figures from West Sussex suggest the current lockdown's impact on traffic is significantly less than during the first restrictions, in March 2020.
County Council traffic counters say road use fell by 34%, compared to a much greater reduction ten months ago.
A West Sussex County Council spokesperson said:
"It's too early to draw firm conclusions but the initial data from nine of our live traffic counters in the county suggests this current National Lockdown has reduced traffic levels on West Sussex roads by about a third."
"We urge residents to remember the travel restrictions are crucial in the fight against Coronavirus spreading.
"Please adhere to the Government's message and only travel if absolutely necessary.
"The first week of this current Lockdown saw a 34 per cent reduction in traffic, compared to an 18 per cent reduction in the second period of national restrictions in November 2020, and a 60 per cent reduction in the first week of the first National Lockdown in the Spring of last year.
"We don't have permanent monitors on every road in the county, so the counters can only provide a "sample" figure and suggest a trend for what's happening on the roads but they do cover a wide geographic spread.
"The nine counters are on A roads in the Broadbridge Heath area (two), Climping, East Grinstead, Findon, Horsham, Shoreham, Southbourne and Worthing.
"It is also worth remembering that restrictions on which businesses and facilities are allowed to open under this current Lockdown are different to those which could continue to trade and operate in the first Lockdown."
More Radio has requested figures from East Sussex, which are still to arrive.