I've been asked to get a breakdown of what is consuming CPU time on our server over an extended period ?

Have been asked about the CPU load on our server and I need to be able to go back to my boss and indicate what % is consumed by what process (or group of processes). I.e. 15% is database activity, 45% is CGI/web pages, 10% is SMTP, 10% is Operational, etc, etc, etc.

Any help really appreciated. System details :
System = SCO_SV
Node = ####
Release = 3.2v5.0.5
KernelID = 98/07/02
Machine = i80386
BusType = ISA
Serial = #########
Users = 5-user
OEM# = 0
Origin# = 1
NumCPU = 4