Although many Studies have shown that the main way in which a portfolio manager might be able to be their Benchmark in a fixed income context is through positioning the portfolio for changes in the level of the interest rates that is predicting parallel shifts in the year of curve. The yield curve does not only move on a parallel way. We can also get a change in the slope of the yield curve which is another important factor in the ways in which portfolio managers might be able to beat their Benchmark this second way in which yield curves might change their shape is through a change in the slope of the yield curve and we refer to this as a Twist in the yield code. There are two ways that we can get a change in the slope of the yield curve. We could have a steepening Twist whether yield curve becomes steeper and there is a bigger difference between short-dated and longer dated bonds yields, or we could have a flattening twist in the yield curve where the yields become closer or maybe even inversely related to each other where you might have that inverted yield curve having shorter dated bonds with higher yields than longer dated bonds. It is possible, but you might get a shift in the yield curve at the same time as you get a Twist in the yield curve and there are some terminology that goes along with this within the bond market. First of all, if we have an upward shift in the yield curve and a steepening Twist, this would be referred to as a bare steepener. The term bear here refers to the fact that we're getting a reduction in the value of bonds interest rates are going up but one prices are going down. So a bear sleep inner is where we think that there's going to be a steeper yield curve at a higher interest rate level generator and this is achieved by interest rates in shorter dated bonds going up by less than interest rates in longer dated bonds. We can also have a bear flattener where we have interest rates going up generally but interest rates at the short end shorter dated bonds are increasing by more than the yields on those longer dated bonds. And of these two the bare flattener is a much more common movement in the yield curve because short-term interest rates are much more volatile than longer term interest rates. The same picture can be seen with downward shifts. So I downward shift with a steepening Twist would be called a bull steepener. This is interest rates going down. So therefore bond prices going up. That's a bull market for our bonds, but a steepening yield curve at the same time. So we're getting a bigger movement at the short end shorter data bonds, and we're getting a full in longer dated bonds yields. And finally, we can have a bull flattener. This is again interest rates falling but we end up with a flatter yield curve at the end because we're getting a bigger movement in those longer dated bonds units and of these two it is the full steep. Another is more common. It is much more common to see bigger movements in the short dated Bond Marketplace, which aren't straight away reciprocated in the longer dated Bond Marketplace. So the bear flattener and ball steepen up are the two more frequently seen yield curve movements out. There. It is possible for a portfolio manager to invest that different points along the yield curve. To benefit from these anticipated changes in the slope of the yield curve. We can use duration to manage the movements in interest rates. Absolutely if interest rates are moving in a parallel fashion, but we can also profit from changes in the slope of the yield curve.