Extent Calculations¶
Use the following calculations when determining the collection extent in linear feet:
| Container | Extent |
|---|---|
| 1 SB | 1 linear foot |
| 1 MB | 0.5 linear feet |
| ½* MB | 0.25 linear feet |
| 1 folder | 0.25 linear feet |
| 1-5 film reel(s)/can(s) | 1 linear foot |
| 1-5 magnetic tape reels | 1 linear foot |
| OS Folder, OS print box, or poster(s) (shelf length) | 3 linear feet |
| OS Folder, OS print box, or poster(s) (half shelf length) | 1.5 linear feet |
No longer used:
| Container | Extent |
|---|---|
| 1 TF | 2 linear feet |
| 1 package | 1 linear foot |
| 1 object | 2 linear feet |
| 1 newspaper | 1 linear foot |
| 1 envelope | 0.25 linear feet |
| 1-5 scrapbooks | 2 linear feet; continue for amounts larger than 5 scrapbooks (e.g., 23 scrapbooks = 10 linear feet, 3) |
Use the following formatting when listing multiple types of extent values:
- # linear feet (# containers or items), # items. # recordings and/or transcripts
- # bytes (# files). Specific file types
½ MBs are distinguished from MBs for extent calculation purposes ONLY. When writing extent statements, list and count ½ MBs as regular MBs.
Examples:
- Collection A has 5 ½ MBs. Extent statement: 1.25 linear feet, 5 MBs.
- Collection B has 2 MBs and 3 ½ MBs. Extent statement: 1.25 linear feet, 5 MBs.