https://libertystreeteconomics.newyorkfed.org/2023/09/how-large-are-inflation-revisions-the-difficulty-of-monitoring-prices-in-real-time/
‘Overly data-dependent’ — how the Fed and the markets keep getting it wrong
https://thehill.com/opinion/finance/4189467-overly-data-dependent-how-the-fed-and-the-markets-keep-getting-it-wrong/
Less widely-appreciated is that the payroll numbers undergo subsequent revisions —sometimes large ones that give the lie to the initial perceptions. Annual benchmark revision of 2022 data, for instance, indicated more robust employment figures than previously reported. In contrast, this year’s early rounds of revisions have consistently been downward.
GDP data also undergo multiple revisions, which makes it hard to quickly ascertain overall macroeconomic conditions. For instance, the Bureau of Economic Analysis will soon release an annual comprehensive update of national accounts, revising GDP data going all the way back to 2013. Furthermore, when estimates of aggregate economic activity provided by GDP and GDI diverge sharply, it introduces an additional layer of uncertainty.
Richard Fisher, a former Dallas Fed president, once offered an example of the dangers involved. Data pointing to excessively low levels of inflation had prompted the Fed to keep rates low in 2002 and 2003. Subsequent revisions, he acknowledged, showed that “inflation had actually been a half point higher than first thought. In retrospect, the real fed funds rate turned out to be lower than what was deemed appropriate at the time and was held lower longer that it should have been.”
The result? Some have argued that the Fed’s loose monetary policy in the early 2000s drove the U.S. housing bubble whose collapse ultimately triggered the 2008 global financial crisis.
Another major dilemma associated with an overly data-dependent approach to monetary policymaking is that three of most important parameters used by central bankers to determine the long-run destination of the economy (r-star, u-star and potential GDP) are unobservable and time-varying. New York Fed researchers, for instance, have highlighted post-pandemic swings in both the short-run and long-run r-star.
Structural shifts involving labor’s bargaining power, globalization, technology, and demographics can also play havoc with fundamental parameter values that are crucial for setting policy.
Central bankers also have to deal with the fact that monetary policy affects the real-economy with a lag of uncertain duration. Intuitively, a reactive Fed that is too focused on backward-looking data will be prone to policy errors, since today’s rate changes will affect the economy only with some lag.
The Fed’s poor forecasting track record does not inspire much confidence in its ability to undertake effective forward-looking monetary policy actions.
Monetary authorities should be more aware of the margin of uncertainty arising from real-world data limitations".