Bump chart: Can I stop missing datapoints from being treated as zero?

[Ginevra House]

I'm trying to make a bump chart visualising where international students from country X go to study. In some years, we have no data from destination countries (Germany, UAE, Malaysia - see attachment), even though they received students from country X.

The bump chart software interprets years of missing data as zero, but that's not correct - there were students, we just don't know how many. Is there any way to stop the script from interpreting missing data as zero, so that the line just starts where there is data, instead of sweeping up from zero?