CDO

Hi
I have 10 files
rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2005.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2006.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2007.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2008.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2009.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2010.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2011.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2012.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2013.monthly.ua.nc
-rwxrwxr-x 1 geeta geeta 38874632 Aug 2 22:05 2014.monthly.ua.nc
Each file contains 3 months data (March to may) (8 variables and 7 levels)(168 records each).
Total records = 1680
I have to calculate seasonal mean (final output should have 56 records consisting of average of each variable onto 7 levels)
For this I used mergetime and then ymonmean
1. cdo -b 32 mergetime 20*.monthly.ua.nc OUT.mergetime.nc
cdo sinfon OUT.mergetime.nc
File format : NetCDF2
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter name
1 : unknown unknown v instant 7 1 115680 1 F32 : z
2 : unknown unknown v instant 7 1 115680 1 F32 : t
3 : unknown unknown v instant 7 1 115680 1 F32 : q
4 : unknown unknown v instant 7 1 115680 1 F32 : vo
5 : unknown unknown v instant 7 1 115680 1 F32 : d
6 : unknown unknown v instant 7 1 115680 1 F32 : u
7 : unknown unknown v instant 7 1 115680 1 F32 : v
8 : unknown unknown v instant 7 1 115680 1 F32 : r
Grid coordinates :
1 : lonlat : points=115680 (480x241)
longitude : 0 to 359.25 by 0.75 degrees_east circular
latitude : 90 to -90 by -0.75 degrees_north
Vertical coordinates :
1 : pressure : levels=7
level : 200 to 1000 millibars
Time coordinate : 30 steps
RefTime = 1900-01-01 00:00:00 Units = hours Calendar = gregorian
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
2005-03-01 00:00:00 2005-04-01 00:00:00 2005-05-01 00:00:00 2006-03-01 00:00:00
2006-04-01 00:00:00 2006-05-01 00:00:00 2007-03-01 00:00:00 2007-04-01 00:00:00
2007-05-01 00:00:00 2008-03-01 00:00:00 2008-04-01 00:00:00 2008-05-01 00:00:00
2009-03-01 00:00:00 2009-04-01 00:00:00 2009-05-01 00:00:00 2010-03-01 00:00:00
2010-04-01 00:00:00 2010-05-01 00:00:00 2011-03-01 00:00:00 2011-04-01 00:00:00
2011-05-01 00:00:00 2012-03-01 00:00:00 2012-04-01 00:00:00 2012-05-01 00:00:00
2013-03-01 00:00:00 2013-04-01 00:00:00 2013-05-01 00:00:00 2014-03-01 00:00:00
2014-04-01 00:00:00 2014-05-01 00:00:00
cdo sinfon: Processed 8 variables over 30 timesteps [0.01s 49MB].

2. cdo ymonmean OUT.mergetime.nc OUT.mergetime.ymonmean.nc
cdo ymonmean: Processed 8 variables over 30 timesteps [2.47s 198MB].

cdo sinfon OUT.mergetime.ymonmean.nc 
   File format : NetCDF2
    -1 : Institut Source   T Steptype Levels Num    Points Num Dtype : Parameter name
     1 : unknown  unknown  v instant       7   1    115680   1  F32  : z             
     2 : unknown  unknown  v instant       7   1    115680   1  F32  : t             
     3 : unknown  unknown  v instant       7   1    115680   1  F32  : q             
     4 : unknown  unknown  v instant       7   1    115680   1  F32  : vo            
     5 : unknown  unknown  v instant       7   1    115680   1  F32  : d             
     6 : unknown  unknown  v instant       7   1    115680   1  F32  : u             
     7 : unknown  unknown  v instant       7   1    115680   1  F32  : v             
     8 : unknown  unknown  v instant       7   1    115680   1  F32  : r             
   Grid coordinates :
     1 : lonlat                   : points=115680 (480x241)
                        longitude : 0 to 359.25 by 0.75 degrees_east  circular
                         latitude : 90 to -90 by -0.75 degrees_north
   Vertical coordinates :
     1 : pressure                 : levels=7
                            level : 200 to 1000 millibars
   Time coordinate :  3 steps
     RefTime =  1900-01-01 00:00:00  Units = hours  Calendar = gregorian
  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss
  2014-03-01 00:00:00  2014-04-01 00:00:00  2014-05-01 00:00:00
cdo    sinfon: Processed 8 variables over 3 timesteps [0.00s 49MB].

3. cdo monmean OUT.mergetime.ymonmean.nc OUT.mergetime.ymonmean.monmean.nc
cdo sinfon OUT.mergetime.ymonmean.monmean.nc
File format : NetCDF2
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter name
1 : unknown unknown v instant 7 1 115680 1 F32 : z
2 : unknown unknown v instant 7 1 115680 1 F32 : t
3 : unknown unknown v instant 7 1 115680 1 F32 : q
4 : unknown unknown v instant 7 1 115680 1 F32 : vo
5 : unknown unknown v instant 7 1 115680 1 F32 : d
6 : unknown unknown v instant 7 1 115680 1 F32 : u
7 : unknown unknown v instant 7 1 115680 1 F32 : v
8 : unknown unknown v instant 7 1 115680 1 F32 : r
Grid coordinates :
1 : lonlat : points=115680 (480x241)
longitude : 0 to 359.25 by 0.75 degrees_east circular
latitude : 90 to -90 by -0.75 degrees_north
Vertical coordinates :
1 : pressure : levels=7
level : 200 to 1000 millibars
Time coordinate : 3 steps
RefTime = 1900-01-01 00:00:00 Units = hours Calendar = gregorian Bounds = true
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
2014-03-01 00:00:00 2014-04-01 00:00:00 2014-05-01 00:00:00
cdo sinfon: Processed 8 variables over 3 timesteps [0.00s 48MB].

problem is that after using monmean, I am still getting 168 records, actually I should get 56 records.

Thanks