If you think that there are any standards on that - you are either too young or indian ( or both). You can right something with 20 lines of code or you can do same shit with only 4 lines. sounds like 20 lines are more productive? No
Where is the negative option? I write new and rewrite shitty exisiting code at the same time, the diff between new & deleted is usually negative. In last 6 months I added 110k LOC while removing 130k LOC per bitbucket metric.
Lines of code don't mean shit. For example I spent 3 days looking to improve performance in an application and at the end of it it was a one line config change that resulted in a 20-30% improvement. There have been many cases where some of my few line changes have had more impact than like 50-100 line changes or more.
While it's not a good metric, it's useful metric. If I notice I've not sent large changes for review,bits almost always I'm working in smaller fixes. Sure there are times when hard changes are small esp perf related, but usually it means not working on "proper" features.