The phrase "availability drop" is correct and usable in written English.
It can be used to describe a decrease in the availability of a product, service, or resource.
Example: "Due to unforeseen circumstances, we are experiencing an availability drop for our latest software update."
Alternatives: "decrease in availability" or "reduction in availability".
Worse still, "as well as the site performing slowly, many visitors were unable to access Twitter at all at this time, with availability dropping from 100% at 1pm to 66.67% at 1.30".
3He was a popular material in neutrons detectors until its availability dropped drastically in 2008.
Energy availability dropped by a factor of 10 to 20 from what it had been between 1991 and 1995.
Hypoxia occurs when oxygen availability drops below the levels necessary to maintain normal rates of metabolism.
Availability dropped off sharply with time; data could be obtained from only two of the 62 oldest papers.
In 2007, the Beijing water availability dropped to 230 m y 1 inh–1, which is only 2.7% of the 8500 m y 1 inh–1 world average.
Fast-growing cells, which are at or near their crowding limit, are therefore driven to utilize glucose exclusively, and only begin to scavenge acetate when glucose availability drops.
Yeasts, fruit flies, nematodes, fishes, hamsters, and several strains of mice as well as rats consistently increase their lifespan when the nutrient availability drops between 30% and 75% of the normal calorie supplementation, according to the species considered.
In the case of N related processes, for example, two calcineurin B-like-interacting Ser/Thr protein kinases, CIPK8 and CIPK23, regulate the expression of nitrate responsive genes, including nitrate transporter encoding genes and genes required for N assimilation, and affect signaling activity when N availability drops [ 41, 42].
