Hull is now more than a month behind London in terms of coronavirus infection rate.
The new findings come as new data shows a greater proportion of people in the city are still being affected by coronavirus, compared to most other places in the UK.
Since lockdown began to ease at the start of May, Hull's average case numbers have continued to fall.
But this is not at the same rate as the neighbouring East Riding, leaving the average number of infected people per 100,000 "trailing somewhat behind".
That is according to University of Hull statistician Dr Michael A. Nolan who has been modelling the latest trends thanks to data supplied daily by the Department for Health.
Despite the downward trend, the graph may provide cause for concern in the city amid Government plans to introduce local lockdowns in areas which are struggling to keep Covid-19 at bay.
"It shows that clear progress has been made in reducing the incidence of confirmed infection, adjusted for size of population," Dr Nolan said.
"Nonetheless, despite achieving reductions of between 70 per cent and 80 per cent, only at the end of this period have Hull and the East Riding seen levels of confirmed infection per 100,000 people fall to about the same level seen in Greater London back on May 3.
"We do still appear to be trailing somewhat behind. Of course, there are other local authorities and regions also lagging behind the progress seen across most of London.
"It is more or less inevitable that different regions will not see progress through a crisis such as this at identical rates."
He also pointed out that many other parts of the UK, use different ways of recording results and have implemented lockdown relaxation in different ways.
Scotland and Northern Ireland appear to have made stronger progress than much of the UK, including Hull and the East Riding.
Despite the concerning trend, no new deaths were added to East Yorkshire's coronavirus death toll on Thursday.
In total, 168 people have lost their lives to Covid-19 between Hull Royal Infirmary and Castle Hill Hospital.
Nationally, that number stands at 39,904 after an increase of 176 was recorded in the 24 hours up until 9am on Thursday.
