                                In the

    United States Court of Appeals
                  For the Seventh Circuit
                      ____________________

No. 18-1897
UNITED STATES OF AMERICA,
                                                    Plaintiff-Appellee,

                                  v.

MICHAEL T. BOSTOCK,
                                                Defendant-Appellant.
                      ____________________

              Appeal from the United States District Court
                   for the Central District of Illinois.
              No. 17-cr-40030-001 — Sara Darrow, Judge.
                      ____________________

 ARGUED NOVEMBER 14, 2018 — DECIDED DECEMBER 10, 2018
               ____________________

   Before EASTERBROOK, SYKES, and SCUDDER, Circuit Judges.
   EASTERBROOK, Circuit Judge. Michael Bostock pleaded
guilty to distributing methamphetamine and has been sen-
tenced to 125 months’ imprisonment, which he contends is
unreasonably high.
   The statute that forbids sales of this drug distinguishes
by its purity. For example, for the purpose of se[ing mini-
mum and maximum sentences, “50 grams or more of meth-
2                                                 No. 18-1897

amphetamine” is treated the same as “500 grams or more of
a mixture or substance containing a detectable amount of
methamphetamine”. 21 U.S.C. §841(b)(1)(A)(viii). The Sen-
tencing Guidelines reﬂect this classiﬁcation. The drug quan-
tity table, U.S.S.G. §2D1.1(c), distinguishes among “Meth-
amphetamine”, “Methamphetamine (actual)”, and “Ice”.
Note (A) to this table says that “methamphetamine” is the
weight of any mixture or substance containing a detectable
amount of the controlled substance; Note (B) deﬁnes the “ac-
tual” variant as the weight of the controlled substance disre-
garding any contaminants or cu[ing agents; Note (C) de-
ﬁnes “ice” as the weight of “a mixture or substance contain-
ing d-methamphetamine hydrochloride of at least 80% puri-
ty.” The Guidelines treat the “actual” and “ice” variants as
ten times the weight of the detectable-quality variant. So, for
example, §2D1.1(c)(5) provides that 500 grams to 1.49 kilo-
grams of methamphetamine, 50 to 149 grams of metham-
phetamine (actual), and 50 to 149 grams of ice all produce an
oﬀense level of 30. Bostock, who concedes distributing 63.8
grams of ice, falls into this category. Given his criminal his-
tory category, the Guidelines recommended a sentence in
the range of 130 to 162 months’ imprisonment.
   The district court sentenced him slightly below the lower
end of this range. Still, he contends that the judge should
have proceeded as if he had sold 64 grams of “methamphet-
amine” rather than 64 grams of “ice.” If the judge had done
that, the recommended sentence would have been in the
range of 77 to 96 months in prison. The judge declined to
disregard the Guidelines’ distinction between “metham-
phetamine” and “ice,” and that decision led to this appeal.
No. 18-1897                                                    3

    Bostock tried to persuade the judge that the distinction
between “methamphetamine” and “ice” (or “methamphet-
amine (actual),” which we ignore from now on) is outmoded
because most sellers have moved to higher-purity products.
He also insisted that the distinction never had a sound em-
pirical footing. Yet the 10-to-1 ratio is baked into the statute.
Although the Sentencing Commission is not compelled to
draw its recommendations from statutory text, it is entitled
to do so, whether or not Congress was legislating in a data-
driven way. The Commission cannot aﬀect statutory mini-
mum and maximum sentences, see Neal v. United States, 516
U.S. 284 (1996), though subject to that constraint it can use
ratios diﬀerent from those that Congress prefers. Id. at 292–
94. Rejecting a legislative ratio is never required, however.
   That holds for judges too. A court may deviate from a
Guideline if persuaded that the Commission is mistaken, see
Kimbrough v. United States, 552 U.S. 85 (2007); United States v.
Corner, 598 F.3d 411 (7th Cir. 2010) (en banc), but is never re-
quired to do so. Indeed, we have held that a district judge is
not required even to articulate a reason for sticking with the
Guidelines and may give the silent treatment to stock argu-
ments asking the court to disregard the Commission’s rec-
ommendations. See, e.g., United States v. Aguilar-Huerta, 576
F.3d 365, 367–68 (7th Cir. 2009); United States v. SchmiB, 717
F.3d 536, 542 (7th Cir. 2013).
   When sentencing Bostock, the district judge did not ig-
nore his challenge to the Sentencing Commission’s decision
to distinguish “methamphetamine” from “ice.” Instead she
explained at some length why she was not persuaded by the
decisions of a few other judges who have treated “ice” the
same as “methamphetamine.” Here Bostock sees an opening,
4                                                  No. 18-1897

for he maintains that the evidence does not support some of
the judge’s statements.
   For example, Bostock contends that the judge erred when
remarking that “ice” is worse than “methamphetamine” be-
cause the purer substance is more valuable, and with “more
value comes more danger.” There’s no record evidence of
extra value, Bostock observes. True enough, but neither does
the record contain evidence to the contrary. (Bostock neither
disputed the judge’s observation, a step that might have
spurred the prosecutor to introduce evidence, nor intro-
duced his own evidence, so our review is for plain error. See
United States v. Oliver, 873 F.3d 601, 607–09 (7th Cir. 2017).)
Judges know that higher-octane gasoline sells for more than
weaker stuﬀ and do not need evidence to infer that this is
true of other products as well. Unless the laws of economics
have been repealed in the Central District of Illinois, 60
grams of a substance that can be cut to produce 500 grams of
10% methamphetamine is worth more than 60 grams of 10%
methamphetamine. The amount of the diﬀerence is unknown
on this record, but the sign on the variable is known.
    Bostock also contends that the judge erred in equating
sellers of “ice” with large-scale dealers. It may well be that
the Commission (and Congress) were inﬂuenced by a belief
that those selling higher-purity drugs are higher in the chain
of distribution, but the district judge did not rely on that be-
lief, which is not necessary to sustain a purity-based distinc-
tion in sentencing. The 10-to-1 ratio between “ice” and
“methamphetamine” does not denigrate from marginal pun-
ishment for more serious criminals. Large-scale dealers op-
erate on, well, a larger scale than 64-gram sales. The Guide-
lines increase the base oﬀense level until it reaches 38 at 4.5
No. 18-1897                                                 5

kilograms of “ice” or 45 kilograms of “methamphetamine”;
kingpins thus receive higher sentences. Bigwigs also receive
enhancements under §3B1.1 for their supervisory roles.
There’s no problem with holding Bostock, who did not re-
ceive a supervisory enhancement, responsible for the
amount or purity of the drug he distributed.
    It is not necessary to go through Bostock’s objections to
the judge’s other statements. The bo[om line is that she
stuck with the distinction between “methamphetamine” and
“ice,” as she was entitled to do. She gave Bostock an indi-
vidualized sentence that depended substantially on his crim-
inal history category of VI—the judge found him undeterra-
ble, with crimes increasing in gravity after each release from
prison—and the need to protect the community from high-
quality methamphetamine made in industrial laboratories in
other places, which had become a plague after police man-
aged to shut down most of the local manufacturers. Bostock
should count himself fortunate, given the judge’s observa-
tions, that his sentence is below rather than above the range
recommended by the Sentencing Commission.
                                                    AFFIRMED
