Select adjacent data based on values in cells

I have a giant Excel file that contains a time column and a data column. In two new columns I'd like to pull the time and the corresponding data (same row) when a new second begins based on the time column's value. The number of rows per second is not consistent, so I can't use a linear offset. The time (A) and data (B) columns are formatted as follows:

Time        Data  
163010.3838 0.009332522  
163010.8468 0.009332853  
163011.3099 0.009332936  
163011.7749 0.00933318  
163012.2399 0.009334042  
163012.7049 0.00933733  
163013.168  0.009335146  
163013.633  0.009332692  
163014.098  0.009335718  
163014.5631 0.009334616  
163015.0271 0.009334818  
163015.4921 0.009336317   
163015.9571 0.009335719

Time is in the format hhmmss.decimal value as seen. In adjacent columns (say C and D) I want to pull the time and data values of each row whenever a new second is reached. So it would look like:

Time   Data  
163010 0.009332522   
163011 0.009332936      
163012 0.009334042

and so forth.