Time Series Components

A time series can be broken into 4 components:

• Trend, $T_t$$\large T_t$
• Cyclical, $C_t$$\large C_t$
• Seasonal, $S_t$$\large S_t$
• Irregular, $I_t$$\large I_t$

Additional Components

• The very low frequency component: $T_t$$\large T_t$
• The medium low frequency component: $C_t$$\large C_t$
• The medium high frequency component: $S_t$$\large S_t$
• The very high frequency component: $I_t$$\large I_t$
• The low frequency component: $T_t+C_t$$\large T_t + C_t$
• The high frequency component $S_t+I_t$$\large S_t + I_t$