FinancialData returns undefined Units for Volume or randomly fails

Question

Recently FinancialData["IBM","Volume"] started failing and when it does randomly work, it returns Quantity[3073167,Shares] but the units "Shares" fails the test: KnownUnitQ["Shares"] returns False. Previously this request returned a number, not a quantity. The same effect happens with FinancialData["IBM","OHLCV"], yet FinancialData["IBM","OHLC"] (no volume) works just fine. This is a new recent behavior. I'm using Mathematica 11.3.0.0

Answer 1

This does appear to be a bug

$Version

(* "11.3.0 for Mac OS X x86 (64-bit) (March 7, 2018)" *)

vol = FinancialData["IBM", "Volume"]

(* Quantity[3073167, "Shares"] *)

As you pointed out,

KnownUnitQ["Shares"]

(* False *)

As a result, QuantityUnit fails

vol // QuantityUnit

(* QuantityUnit[Quantity[3073167, "Shares"]] *)

As does QuantityMagnitude

vol // QuantityMagnitude

(* QuantityMagnitude[Quantity[3073167, "Shares"]] *)

The workaround is to use Part

vol[[1]]

(* 3073167 *)

vol[[-1]]

(* "Shares" *)

Or without defining a variable,

FinancialData["IBM", "Volume"][[1]]

(* 3073167 *)

WolframAlpha has the same issue

WolframAlpha["trade volume for IBM", {{"Result", 1}, "ComputableData"}]

(* Quantity::unkunit: Unable to interpret unit specification Shares.

Quantity::unkunit: Unable to interpret unit specification Shares.

Quantity[3.073*10^6, "Shares"] *)