Similarly, they calculate that only 35 % of benefits spells last one year or less, compared to around 58% of spells with a duration below 12 months reported in Table 9. Even though the benefit receipt rate in urban Rotterdam is two to three times as high as the one for the country as a whole, heterogeneity in spell durations within the country does not appeal' to be responsible for the differences in findings. The postcode information in the SSB data can be used to restrict the sample to recipients who live in city of Rotterdam at the beginning of their spell.