LM_XB403 is the USDA Agricultural Marketing Service report titled "National Daily Boxed Beef Cutout & Boxed Beef Cuts." It is the canonical daily read on wholesale beef pricing. New users find it dense at first because it carries three different views of the same trade activity stacked on one PDF, and the layout has not changed materially in years.
The afternoon edition (LM_XB403) releases each business day around 3 PM Central time (4 PM Eastern), occasionally drifting later if the data office is processing a heavy session. A morning companion report (LM_XB402) releases around 11 AM Central and covers transactions from the prior afternoon through 9:30 AM. The afternoon edition is the version most participants quote when they refer to "the cutout" because it is cumulative across the full session. The data is captured under the Livestock Mandatory Reporting (LMR) program, which obligates large packers to report negotiated sales to USDA. That mandatory basis is what gives the report its weight: it is not a survey of opinion, it is a tally of trades that actually cleared.
The headline section
The first block of the report carries the Choice and Select cutout values for the current session, the change from the prior session, the carcass-weight adjusted load count, and the same fields for the prior session. The cutout values are the synthetic per-cwt numbers built up from yield-weighted primal prices. The load count is the number of 40,000-pound truckloads transacted in the session and reported under LMR. A typical day prints somewhere between 80 and 200 negotiated loads on Choice; a quiet day or a holiday-shortened session prints fewer.
The headline numbers also carry a five-day rolling average and a five-area weighted average that smooths out single-day noise. A buyer who is not actively trading the day can use the rolling average as a saner read of where the market actually sits.
The primal section
Below the headline, the report breaks the cutout down by primal: rib, chuck, round, loin, brisket, short plate, and flank, each with Choice and Select prices and the contribution to the cutout. This is where a buyer looking for the source of a daily move actually looks. A $2/cwt Choice cutout move can be fully explained by a single primal (loins firmed on a feature pull) or distributed across all of them (a broad demand uptick). The two readings imply very different next-session expectations.
Each primal line carries a sub-primal count and a weighted average. Below that, individual sub-primal items appear: ribeyes lip-on (109E and 109A), strip loins boneless (180), tenderloins (189A heavy and light), top butts (184), tri-tips (185D), inside rounds (168), and so on. The IMPS code in parentheses is the institutional spec number; matching that code is how a buyer ties a price line to the cut they actually buy.
Volume and trim sections
After the sub-primal lines, the report shows trim sections for chemical lean items: 50 percent lean, 65 percent, 73 percent, 90 percent, and the various imported trim grades. These items trade thinner and on weekly or sub-daily cadence rather than every session, and a sparse line on a given day is normal rather than alarming.
The volume column on every line is the load count attributed to that specific item or grade for the session, and it is the single most useful field for sanity checking. A primal that prints a sharp price move on one or two loads is information, but it is not strong information. The same move on a dozen loads is much stronger.
Reading it as a buyer
The most efficient way to read LM_XB403 is in three passes. First pass: cutout direction and primary contributor (which primal moved the cutout?). Second pass: sub-primal detail on the cuts you actually buy or feature. Third pass: trim items and load counts to understand whether today's print will hold or fade tomorrow. Most buyers spend less than ten minutes on the report on a quiet day and twenty on an active one. The work the report does for a buyer is most valuable cumulatively, not on any single session.