4-bit floating point FP4

But you still have all the other numbers carrying sign info. This is only the sign of denormals and that's way less valuable. Outside of particular equations it ends up added to something else and disappearing entirely. It would be way better to cut it and have either half the smallest existing positive value or double the largest existing value as a replacement. Or many other options.

Prehistoric information could be preserved by an oral tradition, until it is recorded in some documents (like the Oral Histories at the Computer History Museum site).

So Intel has initiated the discussions for the future IEEE standard with many relevant companies, even before the launch of 8087. AMD was a company convinced immediately by Intel, so AMD was able to introduce a FP accelerator (Am9512) based on the 8087 FP formats, which were later adopted in IEEE 754, also in 1980 and a few months before the launch of Intel 8087. So in 1980 there already were 2 implementations of the future IEEE 754 standard. Am9512 was licensed to Intel and Intel made it using the 8232 part number (it was used in 8080/8085/Z80 systems).

Unlike AMD, the traditional computer companies agreed that a FP standard is needed to solve the mess of many incompatible FP formats, but they thought that the Kahan-Intel proposal would be too expensive for them, so they came with a couple of counter-proposals, based on the tradition of giving priority to implementation costs over usefulness for computer users.

Fortunately the Intel negotiators eventually succeeded to convince the others to adopt the Intel proposal, by explaining how the new features can be implemented at an acceptable cost.

The story of IEEE 754 is one of the rare stories in standardization where it was chosen to do what is best for customers, not what is best for vendors.

Like the use of encryption in communications, the use of the IEEE standard has been under continuous attacks during its history, coming from each new generation of logic designers, who think that they are smarter than their predecessors, and who are lazy to implement properly some features of the standard, despite the fact that older designs have demonstrated that they can in fact be implemented efficiently, but the newbies think that they should take the easy path and implement inefficiently some features of the standard, because supposedly the users will not care about that.

So the 1990s were long after the time when 32-bit FP numbers were normal. FP32 was revived only by GPUs, for graphic applications where precision matters much less.

Already after 1974, the C programming language made double-precision the default FP size, not the 32-bit single-precision size, for the same reason why Intel 8087 introduced extended precision. Single-precision computations for traditional applications are suitable only for experts, not for ordinary computer users.

While before C the programming languages used single-precision 32-bit numbers as the default size, the recommendations were already to use only double-precision wherever complicated expressions were computed.

I have started using computers by punching cards for a mainframe, but that was already at a time when 32-bit FP numbers were not normally used, but only 64-bit FP numbers.

The best chances of seeing 32-bit single-precision numbers in use was in the decade from 1965 to 1975, at the users of cheap mainframes or of minicomputers without hardware floating-point units, where floating-point emulation was done in software and emulating double-precision was significantly slower.

Before the mid sixties, there were more chances to see 36-bit floating-point numbers as the smallest FP size.