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analysis software. The exceedance probabilities in Figure 1 were converted to interval probabilities by subtraction of values at bin boundaries. These results are shown below in Table 2. Table 2 Seismic Hazard Data for Benefit-Cost Analysis Eugene, Oregon Return PGA Bin Annual Interval Period (% g) Probability (years) 4 - 8 0.004179 239 8 - 16 0.002265 442 16 - 32 0.001324 755 32 - 55 0.000273 3,658 55 - 80 0.000047 21,302 80- 100 0.000009 108,950 >100 0.000006 176,612 As an example, the data in Table 2 may be interpreted as follows. For ground shaking between 16% and 32% of g, the annual probability is 0.001324 and this level of ground shaking is expected in Eugene about once every 755 years, on average. 4.0 BENEFIT-COST ANALYSIS: DATA DOCUMENTATION 4.1 Seismic Hazard Data Seismic hazard data for Eugene, Oregon are derived from USGS data, using the same approach as in FEMA's Seismic Hazard Calculator, but using the full USGS seismic hazard curve which is more accurate than the three data points available on the USGS website. Seismic hazard data were presented in full in Section 3.0 above. These data are for a rock site, with a thin layer of firm soil, as appropriate for this facility's location (see Technical Appendix for documentation). 4.2 Data Documentation Summary Data sources and documentation are given in Table 3 below and following text. The following sections contain detailed documentation for building and contents values, building demolition damage percentage, building specific fragility curves, casualty rate estimates (derived from building fragility curves), displacement costs and times, and economic impact of loss of public services provided from the Eugene City Hall.