Instructions and DRAM stats

I see these numbers in the output of a kernel

dram__sectors_read.sum          sector      7,859
dram__sectors_write.sum         sector      8,615
sm__inst_executed.sum           inst        5,116

I would like to know how it is possible when the number of instructions is less that dram transactions? Not all instructions are even memory reference instructions. That means for one load, multiple transactions are send to read from dram.