Total original estimate of blocking work items
Return the sum of the original estimates of the linked work items of the current work item linked with the "is blocked by" link type in hours.
Configuration
Create a Custom smart number field and use the General parsing mode.
Expression
%{sum(append(fieldValue({issue.originalEstimate},linkedIssues("is blocked by")),[0]))
/60}
If the resulting number from the expression contains too many decimal numbers, feel free to select one of the available display formats or to configure it manually.
Format
Default
Used parser functions
The links lead to the JWTC documentation because the parser functions are shared functionalities.