MELSRV MEDLINE AND MEDLINE DATABASES Z39.50 SERVER STATISTICS      
               Time period: 09/01/99 through 09/30/99                           
                                                                                
                                                                                
                                                                                
1.0  SUMMARY STATISTICS                                                         
_______________________                                                         
                                                                                
Relative use of MEDLINE AND MEDLINE databases:                                  
                                                                                
                                                 Number of                      
                                 Searches        Records Presented              
                                 ________        _________________              
    MED (current)                 157,160              8,851,755                
    MED90                          32,060                844,163                
    MED85                          20,533                309,069                
    MED80                          16,285                156,676                
    MED75                          14,179                101,297                
    MED66                          13,891                118,372                
                                                                                
                                                                                
    Per hour usage:                                                             
         Time                    Searches        Records Presented              
    _______________         _____________        _________________              
    12-2  a.m.                      3,174                  102,775              
     2-4  a.m.                      3,157                   70,439              
     4-6  a.m.                        910                   44,111              
     6-8  a.m.                      2,093                   99,744              
     8-10 a.m.                     19,718                  768,613              
    10-12 a.m.                     45,509                1,770,981              
    12-2  p.m.                     46,087                1,847,187              
     2-4  p.m.                     54,006                2,159,232              
     4-6  p.m.                     41,210                1,687,693              
     6-8  p.m.                     20,096                  868,196              
     8-10 p.m.                     11,392                  599,580              
    10-12 p.m.                      6,756                  362,781              
    __________              _____________        _________________              
        Total:                    254,108               10,381,332              
                                                                                
1.1  SEARCH commands                                                            
____________________                                                            
                                                                                
Zero results may indicate no access to the database                             
                                                                                
Number of SEARCH commands issued by location:                                   
Location                                                       Total            
________                                                       _____            
Berkeley                                                       3,159            
Davis                                                          1,570            
Irvine                                                           892            
Los Angeles                                                    3,811            
Riverside                                                        229            
San Diego                                                      6,896            
San Francisco                                                  5,300            
Santa Barbara                                                    185            
Santa Cruz                                                       253            
Lawrence Berkeley                                                747            
Lawrence Livermore                                               160            
Los Alamos                                                         0            
MELWEB                                                       227,377            
Other - UC                                                       390            
Other-Network UC                                               3,139            
                                                               _____            
                                                             254,108            
                                                                                
                                                                                
1.2  Records Presented                                                          
______________________                                                          
                                                                                
Zero results may indicate no access to the database                             
                                                                                
Number of Records Presented by location:                                        
                                                                                
Location                                                       Total            
________                                                       _____            
Berkeley                                                      26,702            
Davis                                                         15,175            
Irvine                                                        14,284            
Los Angeles                                                   46,042            
Riverside                                                      1,640            
San Diego                                                     33,809            
San Francisco                                                 50,181            
Santa Barbara                                                  2,468            
Santa Cruz                                                       172            
Lawrence Berkeley                                              3,245            
Lawrence Livermore                                               647            
Los Alamos                                                         0            
MELWEB                                                    10,148,468            
Other - UC                                                     4,856            
Other-Network UC                                              33,643            
                                                               _____            
                                                          10,381,332            
                                                                                
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                                         0.4                
  Standard deviation in seconds                              1.1                
                                                                                
                                                                                
2.0  MEDLINE AND MEDLINE Databases Detailed Statistics                          
_________________________________________                                       
                                                                                
Median session length (minutes:seconds)                    22:58                
Average session length (minutes:seconds)                   25:11                
Longest session recorded (minutes:seconds)                276:43                
Average number of searches completed per session          254108                
Retrievals per search - median                               4.0                
Retrievals per search - average                            320.4                
Retrievals per search - standard deviation                4179.1                
Percent of searches completed with 0 results                29.1%               
                                                                                
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                                         254,108          11.6%         
  PRESENT                                      1,851,669          84.4%         
  INIT or CLOSE                                   87,001           4.0%         
  OTHER                                            1,335           0.1%         
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         18,374      4.9%   7,048   38.4%       4      712.9   8872.1  
  PERSONAL AUTHOR 85,952     22.7%  22,349   26.0%       6       72.7    578.2  
  TITLE WORD      27,415      7.3%   9,543   34.8%       4      193.8   1677.3  
  SUBSET             985      0.3%     216   21.9%      27      228.8   1572.5  
  SUBJECT WORD     1,643      0.4%     852   51.9%      13      997.1   6886.7  
  SUBJECT          9,188      2.4%   4,673   50.9%      21      714.9   3591.0  
  EXACT SUBJECT   20,429      5.4%   5,130   25.1%      35      452.8   2614.2  
  MAJOR SUBJECT    1,007      0.3%     404   40.1%      26      797.7   3710.3  
  EXACT MAJOR SUBJ 2,039      0.5%     459   22.5%      36      446.2   7654.9  
  EXACT TITLE      2,748      0.7%   1,644   59.8%       1       26.4    459.2  
  TREE NUMBER          1      0.0%       1    100%       0        0.0      0.0  
  EXACT JOURNAL    3,865      1.0%   1,327   34.3%     160     1239.3   2922.3  
  MAJOR TREE NUM       3      0.0%       2   66.7%   1,084     1084.0      0.0  
  CAS                111      0.0%      64   57.7%      20      108.2    298.9  
  KEYWORD         134752     35.7%  39,651   29.4%      18      583.0   5847.1  
  DATE             7,841      2.1%   1,837   23.4%       5      125.2   1137.8  
  LANGUAGE        25,084      6.6%   6,755   26.9%      28      356.7   2472.1  
  UNIQUE ID        1,092      0.3%     236   21.6%       1        6.6    156.7  
  ADDED            2,034      0.5%   1,274   62.6%       6       19.6     37.1  
  PUB TYPE        11,202      3.0%   2,780   24.8%      21      130.1    645.3  
  AUTHOR AFFIL.    2,554      0.7%   1,169   45.8%       8       99.7   1248.5  
  CHEMICAL NAME      106      0.0%      73   68.9%       5       54.3    157.7  
  EXACT CHEMICAL      24      0.0%      22   91.7%       4        4.0      1.4  
  AT              16,242      4.3%   4,789   29.5%      24      506.1   2938.9  
  AGE              1,284      0.3%     270   21.0%      27      154.0    586.5  
  ISN                  0      0.0%       0    0.0%       0        0.0      0.0  
  ARTICLE            561      0.1%     158   28.2%      47      330.3   1443.1  
  XXS                852      0.2%     387   45.4%      22     1560.3   8193.5  
  XMXS               395      0.1%     166   42.0%      22     1097.4   7066.7  
  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       60      0.0%      52   86.7%      55     2071.0   5657.5  
                                                                                
                                                           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        78,284     30.8%  25,759   32.9%       8      266.5   2461.0  
  Single         175,824     69.2%  48,089   27.3%      15      527.7   5670.0  
                                                                                
                                                                                
                                                                                
PRESENT commands, by type:                                                      
  MARC                                                      35.5%               
  OPAC                                                      26.7%