If that's true then you should find some better software.

I think every two years would still be preferable, though yearly should be possible.

I like the indications of BMI brackets. Height would be a good thing to add, though based on the brackets I can tell you're approximately 5'10. I'd have preferred to see age on the X axis instead of year. I think this is an effective way to present the data -- styling could improve beauty, though that is not my forte. If there were relevant events (e.g. started a diet) you could add those to the timeline.