I am looking to analyse primary bond data and need the YTD and Credit Ratings at issuance. For some bonds I used the formula builder and "Yield to Maturity" function to extract YTM at issuance for data. For some, however, it returned "NULL" or an empty row.
What does "NULL" and empty row imply in this context? Is data simply not available or is there an issue with the formula?
Can this issue be solved?
What function or method do you recommend to use to extract bonds' YTM at issuance?
Thanks a lot in advance!