$W_t=|V_{A}\times({S_{A,t'}-S_{A,t}}) + V_{B}\times({S_{B,t'}-S_{B,t}})| \ \ \ t<t'$

$R_t=
\left\{
\begin{array}{ll}
1000\times W_t & if\ spread\ reverse\ to\ mean \\
-1000\times W_t & if\ spread\ reach \ stop-loss \\
-500\times W_t & if\ spread\ force\ exit \\
0 & otherwise
\end{array}
\right.$

### Q1

|Month |ArrDelay| DepDelay| maxDelay|
|----- |--------|---------|----------|
2008-1|1525.0|1355.0|1525.0
2008-2|2461.0|2457.0|2461.0
2008-3|1490.0|1521.0|1521.0
2008-4|2453.0|2467.0|2467.0
2008-5|1951.0|1952.0|1952.0
2008-6|1707.0|1710.0|1710.0
2008-7|1510.0|1518.0|1518.0
2008-8|1359.0|1367.0|1367.0
2008-9|1583.0|1552.0|1583.0
2008-10|1392.0|1369.0|1392.0
2008-11|1308.0|1286.0|1308.0
2008-12|1655.0|1597.0|1655.0

### Q2

|Year| weather delay count|
|----|--------------------|
2000|0
2001|0
2002|0
2003|44620
2004|115989
2005|111388

### Q3

|ArrDelay Rank| IATA airport code|
|-------------|------------------|
1| ATL
2| ORD
3| DFW
4| DEN
5| LAX

|DepDelay Rank| IATA airport code|
|-------------|------------------|
1| ATL
2| ORD
3| DFW
4| LAX
5| PHX