diff --git a/orchagent/port_rates.lua b/orchagent/port_rates.lua
index a6bfaaea0261..37b5ab7f2942 100644
--- a/orchagent/port_rates.lua
+++ b/orchagent/port_rates.lua
@@ -29,6 +29,7 @@ local initialized = redis.call('HGET', rates_table_name, 'INIT_DONE')
 
 logit(initialized)
 
+local n = table.getn(KEYS)
 for i = 1, n do
     -- Get new COUNTERS values
     local in_ucast_pkts = redis.call('HGET', counters_table_name .. ':' .. KEYS[i], 'SAI_PORT_STAT_IF_IN_UCAST_PKTS')
diff --git a/orchagent/rif_rates.lua b/orchagent/rif_rates.lua
index 6c89e5233a27..a2f7e58e317b 100644
--- a/orchagent/rif_rates.lua
+++ b/orchagent/rif_rates.lua
@@ -24,6 +24,7 @@ local delta = tonumber(ARGV[3])
 local initialized = redis.call('HGET', rates_table_name, 'INIT_DONE')
 logit(initialized)
 
+local n = table.getn(KEYS)
 for i = 1, n do
     -- Get new COUNTERS values
     local in_octets = redis.call('HGET', counters_table_name .. ':' .. KEYS[i], 'SAI_ROUTER_INTERFACE_STAT_IN_OCTETS')
@@ -33,7 +34,7 @@ for i = 1, n do
 
     if initialized == "DONE" or initialized == "COUNTERS_LAST" then
         -- Get old COUNTERS values
-        local in_octets_pkts_last = redis.call('HGET', rates_table_name .. ':' .. KEYS[i], 'SAI_ROUTER_INTERFACE_STAT_IN_OCTETS_last')
+        local in_octets_last = redis.call('HGET', rates_table_name .. ':' .. KEYS[i], 'SAI_ROUTER_INTERFACE_STAT_IN_OCTETS_last')
         local in_pkts_last = redis.call('HGET', rates_table_name .. ':' .. KEYS[i], 'SAI_ROUTER_INTERFACE_STAT_IN_PACKETS_last')
         local out_octets_last = redis.call('HGET', rates_table_name .. ':' .. KEYS[i], 'SAI_ROUTER_INTERFACE_STAT_OUT_OCTETS_last')
         local out_pkts_last = redis.call('HGET', rates_table_name .. ':' .. KEYS[i], 'SAI_ROUTER_INTERFACE_STAT_OUT_PACKETS_last')