August 15, 2017 at 12:05 pm #29458
Thank you for the follow-up.
The answer has three parts:
- "yd" is not a short-form combination and so would not require an ELI regardless.
- A short-form combination like "yr" (for "year") would need an ELI according to Nemeth Code
- If "yr" (or a similar abbreviation that corresponds to a short-form combination) were used within Nemeth Code switch indicators, then you are correct that we should use the ELI with it when it is in a "single letter" circumstance as defined by the Nemeth Code.