MELSRV MEDLINE AND MEDLINE DATABASES Z39.50 SERVER STATISTICS      
               Time period: 04/01/99 through 04/30/99                           
                                                                                
                                                                                
                                                                                
1.0  SUMMARY STATISTICS                                                         
_______________________                                                         
                                                                                
Relative use of MEDLINE AND MEDLINE databases:                                  
                                                                                
                                                 Number of                      
                                 Searches        Records Presented              
                                 ________        _________________              
    MED (current)                 173,840              9,972,231                
    MED90                          27,352              1,003,040                
    MED85                          13,567                373,453                
    MED80                           7,740                203,305                
    MED75                           5,032                123,931                
    MED66                           4,585                101,859                
                                                                                
                                                                                
    Per hour usage:                                                             
         Time                    Searches        Records Presented              
    _______________         _____________        _________________              
    12-2  a.m.                      2,753                  126,072              
     2-4  a.m.                      1,471                   40,124              
     4-6  a.m.                        465                   25,111              
     6-8  a.m.                      2,117                  102,153              
     8-10 a.m.                     16,960                  823,817              
    10-12 a.m.                     37,933                1,832,818              
    12-2  p.m.                     40,957                2,082,916              
     2-4  p.m.                     48,693                2,328,329              
     4-6  p.m.                     38,736                1,986,880              
     6-8  p.m.                     20,394                1,164,865              
     8-10 p.m.                     13,309                  798,527              
    10-12 p.m.                      8,328                  466,207              
    __________              _____________        _________________              
        Total:                    232,116               11,777,819              
                                                                                
1.1  SEARCH commands                                                            
____________________                                                            
                                                                                
Zero results may indicate no access to the database                             
                                                                                
Number of SEARCH commands issued by location:                                   
Location                                                       Total            
________                                                       _____            
Berkeley                                                       3,078            
Davis                                                          2,257            
Irvine                                                           966            
Los Angeles                                                    2,670            
Riverside                                                         76            
San Diego                                                      3,369            
San Francisco                                                  6,379            
Santa Barbara                                                    134            
Santa Cruz                                                       273            
Lawrence Berkeley                                                135            
Lawrence Livermore                                                48            
Los Alamos                                                         0            
MELWEB                                                       208,681            
Other - UC                                                       585            
Other-Network UC                                               3,465            
                                                               _____            
                                                             232,116            
                                                                                
                                                                                
1.2  Records Presented                                                          
______________________                                                          
                                                                                
Zero results may indicate no access to the database                             
                                                                                
Number of Records Presented by location:                                        
                                                                                
Location                                                       Total            
________                                                       _____            
Berkeley                                                      23,033            
Davis                                                         22,563            
Irvine                                                         9,740            
Los Angeles                                                   29,448            
Riverside                                                        456            
San Diego                                                     15,257            
San Francisco                                                 55,157            
Santa Barbara                                                    716            
Santa Cruz                                                       390            
Lawrence Berkeley                                              1,563            
Lawrence Livermore                                               548            
Los Alamos                                                         0            
MELWEB                                                    11,582,727            
Other - UC                                                    12,851            
Other-Network UC                                              23,370            
                                                               _____            
                                                          11,777,819            
                                                                                
1.3  Response time                                                              
__________________                                                              
                                                                                
Search response time from receipt of search request                             
DLA until transmission of search response:                                      
  Average in seconds                                         1.5                
  Standard deviation in seconds                              6.9                
                                                                                
Present response time from receipt of present request                           
DLA until transmission of a present response:                                   
  Average in seconds                                         0.3                
  Standard deviation in seconds                              0.7                
                                                                                
                                                                                
2.0  MEDLINE AND MEDLINE Databases Detailed Statistics                          
_________________________________________                                       
                                                                                
Median session length (minutes:seconds)                    24:26                
Average session length (minutes:seconds)                   27:16                
Longest session recorded (minutes:seconds)                254:07                
Average number of searches completed per session             0.0                
Retrievals per search - median                               5.0                
Retrievals per search - average                            446.5                
Retrievals per search - standard deviation                4865.4                
Percent of searches completed with 0 results                27.4%               
                                                                                
Percent of searches entered that are long                    0.0%               
Percent of long searches completed                                              
  (includes partial results)                                 100%               
                                                                                
Commands entered, by type, excluding errors:                                    
                                                   Total     Percentage         
                                              __________     __________         
  SEARCH                                         232,116           9.5%         
  PRESENT                                      2,151,688          88.2%         
  INIT or CLOSE                                   55,772           2.3%         
  OTHER                                            1,173           0.0%         
SEARCHes completed:                                        RETRIEVALS PER NON-  
                             TOTAL    ZERO RESULTS        ZERO RESULT SEARCHES  
                     _____________  ______________      ______________________  
                              % of            % of                              
                               all         all for                        Std.  
                     No.  SEARCHes     No.   Index  Median       Avg.     Dev.  
                  ______ _________  ______ _______  ______ __________  _______  
  By index:                                                                     
  JOURNAL         18,122      5.0%   8,053   44.4%       4      703.7   3054.2  
  PERSONAL AUTHOR 74,695     20.7%  21,080   28.2%       8       89.5    853.1  
  TITLE WORD      27,524      7.6%  10,718   38.9%       4      186.4   1656.8  
  SUBSET             763      0.2%     156   20.4%      35      937.7   6714.4  
  SUBJECT WORD     3,774      1.0%   2,156   57.1%      15     2749.9  17719.2  
  SUBJECT          9,450      2.6%   4,533   48.0%      23      751.0   4797.3  
  EXACT SUBJECT   19,587      5.4%   4,118   21.0%      49      669.7   3107.4  
  MAJOR SUBJECT      683      0.2%     270   39.5%      19      290.4   1012.6  
  EXACT MAJOR SUBJ 2,189      0.6%     379   17.3%      25      204.5    592.3  
  EXACT TITLE      2,293      0.6%   1,264   55.1%       1       14.3    147.6  
  TREE NUMBER          0      0.0%       0    0.0%       0        0.0      0.0  
  EXACT JOURNAL    4,036      1.1%   1,386   34.3%     307     1576.1   3278.7  
  MAJOR TREE NUM       0      0.0%       0    0.0%       0        0.0      0.0  
  CAS                 74      0.0%      27   36.5%      15       61.6     88.7  
  KEYWORD         123524     34.2%  29,321   23.7%      24      792.6   6955.7  
  DATE             7,955      2.2%   2,623   33.0%       9      228.7   3815.4  
  LANGUAGE        26,015      7.2%   5,932   22.8%      40      662.1   4643.0  
  UNIQUE ID          875      0.2%     130   14.9%       1        3.5     66.6  
  ADDED            1,096      0.3%     889   81.1%       6       20.6     46.8  
  PUB TYPE        10,103      2.8%   2,007   19.9%      28      229.3   1911.4  
  AUTHOR AFFIL.    3,055      0.8%   1,430   46.8%       9      123.1   1079.9  
  CHEMICAL NAME       73      0.0%      43   58.9%       9      311.1   1080.3  
  EXACT CHEMICAL      19      0.0%      14   73.7%      22       44.2     57.4  
  AT              22,826      6.3%   6,131   26.9%      38      841.3   5223.0  
  AGE              1,044      0.3%     256   24.5%      28      174.8    554.8  
  ISN                  3      0.0%       3    100%       0        0.0      0.0  
  ARTICLE            594      0.2%     100   16.8%      58      482.7   2346.2  
  XXS                741      0.2%     336   45.3%      29      845.5   3298.2  
  XMXS               351      0.1%     167   47.6%      24      510.8   2018.8  
  XS 2                 0      0.0%       0    0.0%       0        0.0      0.0  
  MXS 2                0      0.0%       0    0.0%       0        0.0      0.0  
  Other indexes       10      0.0%       5   50.0%  11,096    11096.0      0.0  
                                                                                
                                                           RETRIEVALS PER NON-  
                             TOTAL    ZERO RESULTS        ZERO RESULT SEARCHES  
                     _____________  ______________      ______________________  
                              % of            % of                              
                               all         all for                        Std.  
                     No.  SEARCHes     No.   Index  Median       Avg.     Dev.  
                  ______ _________  ______ _______  ______ __________  _______  
  By number of indexes:                                                         
  Multiple        81,372     35.1%  26,268   32.3%      12      473.7   3838.3  
  Single         150,744     64.9%  37,422   24.8%      18      684.3   6415.2  
                                                                                
                                                                                
                                                                                
PRESENT commands, by type:                                                      
  MARC                                                      31.9%               
  OPAC                                                      28.8%