I think in the legend, 2021 should be 2027 and 2017 should be 2021. Otherwise I doesn't make sense to me. Maybe someone wrote by accident 2017 instead of 202

I think in the legend, 2021 should be 2027 and 2017 should be 2021. Otherwise I doesn't make sense to me. Maybe someone wrote by accident 2017 instead of 2027 and then swapped the legend so that it fits the graph's message. Still, wondering why 6 co-authors, one editor and several peer-reviewers didn't notice it. Or am I getting the graph wrong?