28
You average 4.0 CS per minute as Mid; Gold players average about 5.8. Every 15 CS is roughly a kill worth of gold. Practise last-hitting under tower, shove the wave before recalling, and catch side waves between fights instead of standing in lane doing nothing.
You take part in 28% of your team's kills; Gold players average 53%. After your first item, look to rotate for dragon, grubs and herald, and keep Teleport for fights rather than for farming.
You spend 13% of your games dead. Late deaths cost a minute each; when a fight is lost, back off and defend rather than adding one more death to it.
