Following discussion in
Peerage & Baronetage deaths & births 2023 I thought it would be useful to collate the deaths of high ranking peers in one list
Some confirmations of some comments: it is highly unusual for there to be two consecutive calendar years (2022/23) with 0 high ranking deaths in the peerage, though I am counting the late Queen's death in my listing. But focussing just on Dukes, 2 consecutive calendar years without a death is relatively common (there are 9 pairs, and 3 trios of years where this happens).
The following years had 0 deaths in any category: 2023, 2018, 2008, 1998, 1986, 1982, 1966, 1958. So 8 times in 72 years, or 1 in 9.
1988 was a particularly bad year for deaths: 4 Dukes (incl Newcastle-under-Lyme twice, with its resulting extinction) & 2 Marquesses. Also this year holds the record for the shortest length of time between two deaths: 3 days between the 13th Duke of St Albans and 10th Duke of Northumberland.
1954 is the "runner up" with 5 deaths (3 Dukes, 2 Marquesses). These include the 2nd Duke of Albany, whose title had been suspended in 1919. I include as the 2nd Duke had succeeded to the title at birth in 1884, so had enjoyed the title. I do not include the Cumberland & Teviotdale dukes as the last person (the 3rd Duke) to enjoy the title died 1923.
I hope other users find this listing useful.