The dollar is heading into a week packed with economic data releases, with CPI, PPI, and retail sales all scheduled to roll out on Wednesday and Thursday. While these indicators are the core focus for the market, an even more noteworthy phenomenon is the sudden breakdown in the linkage between the dollar and US short-term Treasury yields.

For most of this year, the two moved in positive lockstep. But after entering October, the correlation deteriorated sharply. Even as the sharp September rise in Treasury yields saw a partial pullback and market expectations for further Federal Reserve monetary tightening cooled, the dollar still maintained its strengthening momentum. Were it not for renewed concerns over France's public finance problems dragging down the euro, the dollar's current price level would most likely be significantly lower. With multiple variables intertwined, this week's macro data and European debt market dynamics will jointly determine the dollar index's subsequent direction.

The dollar index and Treasury yield linkage falls apart, correlation indicators weaken markedly

The weakening linkage between the dollar index and US short-term Treasury yields can be seen directly in correlation statistics. At the end of September, the 10-period rolling correlation between the dollar index and the US two-year Treasury yield was +0.66, while the 20-period rolling correlation stood at +0.55. By the end of last week, those two readings had fallen to -0.39 and +0.19 respectively. The mid-section of the five-year Treasury yield curve showed similar changes, indicating that this divergence is not confined to the short end of the bond market.

Since the end of September, the dollar index has risen about 0.75%, while the two-year US Treasury yield has fallen 9.6 basis points over the same period, and the five-year US Treasury yield has dropped 6.8 basis points. Against a backdrop of declining yields, the dollar strengthened against the trend, breaking the previous trading logic.

Fed rate hike expectations cool, euro weakness supports dollar resilience

Earlier this month, US nonfarm payrolls data came in weaker than expected, and combined with several Fed officials actively signaling to offset market expectations for another rate hike in October, market pricing for further monetary tightening was revised lower. Data shows that cumulative rate hike expectations through the end of next year have fallen from slightly above 100 basis points in mid-September to about 80 basis points.

If the dollar continued its earlier positive relationship with short-term Treasury yields, it should have weakened in the current environment. But exchange rate moves are not determined solely by US domestic factors. The market is again worried about France's public finance condition and fears that risk could spill over into other European sovereign bond markets. Combined with rising energy prices, multiple factors continue to weigh on the euro. The euro carries a weight of 57.6% in the dollar index, and the euro's persistent weakness is the core reason the dollar has remained resilient even as Treasury yields decline and rate hike expectations cool.

CPI data brings volatility, but hard to lock in a one-way dollar direction

A large batch of US economic data is being released this week, yet looking back at historical patterns, it is difficult to rely on past regularities to predict the dollar's trend direction. A study reviewing market performance after 188 CPI releases since 2011 found that on the day inflation data is published, the dollar's fluctuation range typically widens, but there is no stable pattern, making it impossible to determine whether the market will continue its prior trend or reverse. This means traders must not only closely track upcoming US economic data, but also European bond market dynamics, whose influence on the dollar's subsequent performance is on par with US domestic inflation data.

Conclusion

Overall, the dollar faces multiple tests in this data-heavy week. The divergence between Treasury yields and the dollar's movement reveals that the core driver of the dollar's current strength comes from the euro's weakness, rather than US rate hike expectations. The upcoming CPI data will amplify short-term volatility, but it is unlikely to directly trigger a one-way move. Next, investors need to watch on two fronts: keeping a close eye on US inflation, retail sales, and other economic data on one hand, while continuously tracking European sovereign debt market risks on the other. Changes in these two areas will jointly determine whether the dollar index can complete an upward breakout. Dollar index daily chart Source: Yihuitong Two-year US Treasury yield daily chart Source: Yihuitong As of 14:46 Beijing time on October 12, the dollar index stood at 102.18.