This year saw the largest ever number of unmet applications for Jewish children wanting to study at a Jewish school in north-west London or south Hertfordshire, a new report has shown.

Analysts at the Institute for Jewish Policy Research (JPR) said that the cluster of Jewish secondary schools within seven miles of each other – JFS, JCoSS, Hasmonean, Yavneh and Immanuel – were still heavily oversubscribed.

This year saw 1,053 applications to Jewish state schools in that area, but only 799 admissions, meaning that more than one in five Jewish children are now being left disappointed – the highest figure on record.

Describing the situation as “particularly acute,” researchers Daniel Staetsky and Jonathan Boyd said applications to JCoSS had been “in excess of 600 each year since it was established,” but that the school was only able to offer 180 places. They noted that these applications were not necessarily first-choice preferences.

Last year both Hasmonean and Yavneh agreed to lay on additional classes in the academic year 2016/17 in order to relieve pressure, which pushed up total state school admissions for the year from 949 to 996, with places offered at Immanuel College, the private fee-paying school, closing the gap between demand and supply.

But the overall figures for supply include Kantor King Solomon in Redbridge, which the authors describe as a “geographical outlier” in an area with an ageing and declining Jewish population, meaning that the main pressure is to the west.

“The situation is particularly acute in North West London and South Hertfordshire, even taking into account the contribution to admissions made by Immanuel,” write the co-authors of the report, published this week.

“Furthermore, the gap between applications and admissions has been noticeably greater in the past three years than it was in the three years prior to that, suggesting that the deficit of places in Jewish secondary schools in and around London may be becoming more acute over time.”

Jewish parents have repeatedly voiced their frustrations about a lack of places in Jewish schools in the area, and this week the community welcomed the prospect of a new Jewish free school in 2018-19, after rival projects agreed to merge.

The JPR report was commissioned by Partnerships for Jewish Schools (PaJeS) after acknowledging “growing concern” about the number of places in Jewish schools in areas with the largest Jewish communities in the capital.

Policy-makers were this week told to “monitor the situation very carefully over the coming few years to ensure that existing capacity is adjusted appropriately each year to accommodate anticipated demand”.

Given that the data “conclusively demonstrate an undersupply of places,” community leaders were warned that the issue “ought to be addressed by expanding capacity in an appropriate way”.