Table 5. Normalized multipliers, i.e. the multipliers for Sweden, Denmark and The Netherlands from the five different data sources, divided by the multipliers for Sweden.

Data source	Normalized multipliers
	Sweden	Denmark	Netherlands
1. Sero-incidence	1	2.16	7.94
2. Travel data I	1	1.80	7.70
3. Travel data II	1	8.80	52.60
4. Reconstruction of the surveillance pyramid	1	1.70	2.00
5. Expert opinion/reconstruction of the surveillance pyramid	1	1.67	2.67